♪♪ -We're sailing around the UK in a historic tall ship to explore its secret islands, to discover the untold stories of the history, cultures, and wildlife that they hold.

♪♪ From 5,000-year-old ruins to fascinating living cultures with links to Viking heritage.

These are found across the 6,000 islands that make up the United Kingdom.

♪♪ In our journey, we're hoping to unveil the mystery of the islands that formed the British Isles.

♪♪ So join us in this voyage of discovery to Britain's secret islands.

♪♪ -Our journey starts in Greenwich as we board the Pelican of London.

This tall ship was launched in 1948, and the crew know the waters around the British Isles very well.

♪♪ For hundreds of years, mariners in tall ships like the Pelican sailed from the Royal Naval College at Greenwich on great expeditions to explore remote corners of the world.

♪♪ Now our journey will take us 500 kilometers north to the Farne Islands and then to Bass Rock, on to the Shetland Islands, the Fair Isle, and finally the Orkney Islands, 1,000 kilometers north of London.

♪♪ Our first stop is the Farne Islands off the coast of Northumberland.

♪♪ Divided into two island groups, inner and outer, the most distant islands are nearly 8 kilometers from the mainland.

For thousands of years, people across Europe, from Scandinavia to Italy, have settled on these remote islands.

What they left behind were layers of history stretching back 5,000 years.

♪♪ In the 7th century, monks settled on the islands, and they became a key site for the birthplace of Christianity in the British Isles.

Lindisfarne Priory was founded by the monks and became a base from which Christian missionaries would evangelize the north of England.

The most famous of the early bishops was Cuthbert, who came to Lindisfarne in the 1670s.

His body was later reburied in a large shrine, and he was made a saint.

Taking refuge amongst the ruins, the islands are a haven for wildlife, including massive colonies of seabirds and the largest population of gray seals in the UK, with up to 4,000 individuals.

♪♪ The abundance of nature served as food for the monks and the early Christian communities.

♪♪ Seals were hunted for their pelts, as well as for meat, and the multitude of seabirds and their eggs supported the religious communities.

♪♪ During his life, Saint Cuthbert would establish an important and far-reaching legacy.

Amongst other acts, he introduced special laws in 676, protecting the eider ducks and other seabirds nesting on the islands.

These are thought to be some of the earliest bird protection laws anywhere in the world.

[ Birds squawking ] ♪♪ Saint Cuthbert would have another far-reaching effect as miracles were reported at his shrine, and Lindisfarne quickly became a center for pilgrimage.

♪♪ The Christian evangelicals lived in peace on this tiny, exposed outcrop of islands.

But the serenity and isolation that drew the monks also made them vulnerable to attack.

And their life was about to be shattered with the arrival of the Vikings.

[ Indistinct shouting ] ♪♪ The Viking ships made off with the treasures and riches from the priory.

♪♪ In the following decades after the raid on the priory, Viking attacks spread across Britain, especially to the north.

We're following in the Vikings' wake, heading 80 kilometers north towards Bass Rock in the Firth of Forth.

Lying northeast of North Berwick, it's a pinprick of land about the size of five football pitches.

And we're greeted with a similar sight to what the Vikings would have seen.

From a distance, the whole island looks white, but as the ship gets closer, it becomes clear that the white covering on the rocks is actually gannets.

The whole island is completely covered with them.

The first person to inhabit Bass Rock was a monk named Baldred from Lindisfarne Priory, sent out in the 8th century to convert the heathens to Christianity.

♪♪ He used the island for meditation and prayer.

And a chapel was built and dedicated in his honor in the 15th and 16th centuries.

♪♪ Around this time, a castle was erected with a small garrison of 100 men, whose role was to defend the Firth of Forth.

Today, only some sections of the castle wall remain, upon which a lighthouse was built.

♪♪ The volcanic crag also served as a prison, when King James I imprisoned his political enemies, including his own uncle Walter Stewart, the Earl of Atholl.

♪♪ Many religious and political prisoners, including royals, ministers, and Jacobites, were locked up here, exiled and forgotten in this gloomy mass of stone and basalt known as the Scottish Alcatraz.

Today, the prisoners have long gone, and the island is home to the largest population of northern gannets.

[ Birds squawking ] ♪♪ Many of them perch and nest on the ruins of the castle and Saint Baldred's Chapel.

[ Birds continue squawking ] This noisy cacophony is at its peak during the breeding season.

♪♪ There are likely to be 75,000 breeding pairs.

That's 10% of the world's population crowded here on this rock.

Just like on the Farne Islands, the birds and their eggs provided an important resource for the local community.

They were prized by the Vikings because of their tender meat, and in the 19th century, people visited the island to shoot the seabirds as they nested.

Eggs were collected, and the young gannets, called gugas, were considered delicacies.

Not only were the hermits, monks, and prisoners fed by the gannets, but they were also sold as sea geese, smoked and wrapped in leaves and then transported to London to be sold in restaurants.

[ Birds continue squawking ] By 1850, almost 2,000 birds were harvested from the rock each year.

Bass Rock is home to over 150,000 gannets.

It's the world's largest breeding colony of northern gannets, and these birds roam over hundreds or even thousands of kilometers.

So even though this island is a pinprick of rock in the sea, it's incredibly important for these birds roaming over such a vast area.

The island is a key wildlife refuge because of the lack of predators.

♪♪ Such concentrations of seabirds cannot survive on the mainland, as their eggs and chicks would be eaten by foxes and rats, which are absent here on Bass Rock.

But the gannets here do face growing threats, including plastic waste.

There are bits of plastic all around these nest areas.

The gannets bring in bits of seaweed to make their nests, but lots of bits of plastic really resemble the seaweed.

So this gets carried up to the island, and that's part of the problem.

Maggie Sheddan, from the Scottish Seabird Centre in North Berwick, has spent the last 21 years rescuing gannets from fishing nets and plastic before releasing them back into the wild.

And the work keeps her very busy.

-There's usually several a year, yes.

Now, I think this bird we saw perhaps a month, six weeks ago.

We couldn't get it.

So it's managed to eat, but it was completely caught in the gate, so it must have been cutting in there.

Often, it's fishing line with a hoop, and that's even worse, 'cause you'll often see it in the bill.

-Sadly, she does see some fatalities.

-At times, yes, 'cause this is ocean litter.

This is -- This is from fishing.

This is from people discarding things.

But for as far as sort of shoreline garbage, we're not seeing as much here.

Your beach cleans, I think, are making a difference.

Because we have a lot of seaweed banks here, gannets do bring a lot of seaweed in, and we do a lot of beach cleans.

We are not seeing as much litter as we used to.

-Okay.

That's good.

The sea of gannets on Bass Rock are testimony to the abundance of fish in the waters nearby.

♪♪ The gannets have evolved secret weapons to catch their prey.

They have binocular vision and can spot fish from up to 30 meters in the air.

[ Birds continue squawking ] They fold back their wings, lock their spines, and hit the water like arrows up to 90 kilometers per hour.

They also have special shock absorbers in their heads and necks.

♪♪ And their razor-sharp beaks and streamlined bodies pierce the water.

♪♪ The momentum of their dives takes them down to about 3 meters below the surface, but they can use their wings and feet to swim 15 meters deep.

They have excellent vision underwater and can swallow fish whole.

But perhaps their most amazing trick of all is that they can take off as soon as they reach the surface, their oily feathers absorbing hardly any water at all.

And when one gannet spots food, hundreds usually follow, all eager to snatch a meal.

♪♪ Despite their highly specialized adaptations to hunt fish, gannets have learned to recognize fishing vessels and follow fishermen for kilometers to eat bycatch and discards.

While many seabirds are in decline, gannets are bucking the trend, and their numbers are increasing year on year.

As Bass Rock is already pretty much full, new breeding colonies of gannets are spreading to other islands nearby.

♪♪ Including the Shetland archipelago, which is the next stop in my journey.

♪♪ Shetland is an ancient landscape made up of about 100 windswept islands.

The capital is Lerwick, with a population of about 7,500, which is 1/3 of the island's total inhabitants.

The land was colonized by the Vikings in the 9th century and only became part of Scotland in the 15th century.

Shetland's place names reflect its Norse history and unique cultural identity shaped by the Vikings.

♪♪ The islands are a treasure trove, with thousands of archeological sites, and none are more impressive than Jarlshof, which is one of the best preserved prehistoric sites in Europe.

♪♪ Shetland was the gateway for the Viking conquest of the North Atlantic, because of its fertile land and proximity to Scandinavia.

The Norsemen arrived looking for land to conquer, and the Viking-Age ruins here are the largest in the British Isles.

♪♪ The remains of the Viking settlements are still visible today, such as this rectangular longhouse at Jarlshof.

At least 12 generations occupied this site and many other villages nearby.

The Vikings initially built wooden houses similar to their villages in Scandinavia.

But perhaps for the scarcity of trees here, they soon adapted to stone dwellings with perforated roofs for insulation.

♪♪ It's easy to imagine the raucous fireside feasts and the smoky atmosphere inside the Viking longhouses across the Shetland Islands, dark outside during the long winter, but warm and noisy in here.

♪♪ The rectangular structures of the longhouse are characteristic of a Norse settlement and the core of a farming complex.

♪♪ [ Indistinct conversations ] Each year, the community of the Shetland Islands comes together and the streets of Lerwick light up as the Up Helly Aa Fire Festival begins.

This is no cultural showcase put on for tourists, but a profoundly deep rooted local custom and ceremony that has evolved over the centuries.

[ Indistinct conversations ] ♪♪ [ Cheers and applause ] Up Helly Aa marks the end of Yule.

♪♪ And over 1,000 guizers carrying fire torches in 47 squads march through the city, some dressed in Norse costumes and singing old songs.

[ All chanting ] A replica Viking longship is paraded through Lerwick, and the climax of the fire festival comes as more torches are lit.

And the longship is burnt to bid farewell to the year past.

♪♪ The fire festival celebrates the changing season, the strength of the community, and the promise of spring to come.

It's easy to remember that the Shetland Islands lie closer to Oslo than to London.

The festival lights up the night sky, along with spectacular displays of the aurora borealis.

Viking legends believed these northern lights were earthly manifestations of their gods.

The lights were seen to be reflections of the shields and armor of Valkyries, female warriors on horseback, who played a significant role in the Norse afterlife.

Whatever their interpretation, they are still here today, and we see the same skies as the Vikings did and experience the same magic of witnessing the aurora lights dance across the night sky.

♪♪ [ Pony neighs ] Ponies are also known to have lived on the Shetland Islands for thousands of years before the Vikings arrived, and they have also adapted to the harsh conditions here.

The islands are world-famous for them, and there's nobody better to answer questions than Elaine Tait, who looks after around 200 Shetland ponies.

-So, as you can see, this is little and large here.

We breed Shetland ponies here at the Merkisayre Stud for 27 years.

-Wow!

-And he is one of our standards.

As you can see, there's a huge height difference.

-Elaine explains how the ponies originated.

-There's evidence of small ponies in Shetland from the Bronze Age.

Food would have been scarce.

The littler ponies wouldn't have needed so much to sustain them.

Also, the weather would have been quite harsh, and the littler ponies could get better shelter.

-The ponies were worked hard by the local communities.

-They were used to cart peats.

So they used to put the kishies on them and cart the peats.

They also used to take seaweed from the beaches.

Like, harvesting seaweed.

They were used for that.

A lot of the stud farm then to try and improve the breed and using the strongest, best stallions to get the stronger ponies for going down the mines and pulling the coal tubs.

-Shetland ponies are well-adapted to the environment up here.

They actually have a double winter coat so that even if they get completely wet and soaking, inside, deep down in the hairs, the inner layer is perfectly dry and keeps them nice and warm.

They also have a long, distinctive mane that protects them from even the harshest conditions.

The scarcity of food across the Shetland Islands is the reason why the ponies are so small.

Smaller bodies need fewer calories.

They're an example of island dwarfism, where animals living on islands with limited food adapt by reducing in size.

♪♪ ♪♪ The Shetland landscape is dotted with mysterious round structures called brochs.

They're still not completely understood today, their purpose being something of a mystery.

Brochs have been likened to the equivalent of Iron Age castles, with double-layered drystone walls for defense.

But it's believed that they also served as lookout towers to watch for approaching danger.

And it's been suggested that they acted as status symbols for Iron Age chieftains as a measure of prestige and standing.

They likely served all of these roles to varying degrees.

This broch is on the shore of Clickimin Loch.

All brochs have a single entrance and are located in places which are hard to reach.

This has led some archeologists to believe that they were a place of refuge for Iron Age communities and their livestock during times of conflict.

♪♪ On the small island of Mousa is one of the best-preserved and most intact of all the brochs in Scotland.

When the Vikings arrived in the ninth century, it had already been standing for over 1,000 years.

Rising 13 meters tall, it's famous as a home to a mysterious nocturnal creature.

The animals that live in Mousa Broch only come out at night.

These strange shapes and dark silhouettes are storm petrels.

Storm petrels have really sensitive eyesight, so to see them up close, you need a special light.

[ Cackling, chirping ] The whole broch is reverberating with the sound of petrels.

You can hear them within the structure of the walls.

[ Cackling, chirping continues ] Storm petrels are Europe's smallest seabirds, being about the size of a sparrow.

They nest in the gaps within the broch's walls and only land during the breeding season, with each female laying a single egg.

They were considered ill omens by ancient mariners, their appearance heralding an approaching storm.

The broch and nearby parts of Mousa Island are home to one of the U.K.'s largest breeding colonies, with around 11,000 breeding pairs, representing about 8% of the entire U.K.'s population.

These tiny migratory birds travel hundreds of kilometers and are also one of the most long-lived seabirds, with one individual recorded over 38 years.

♪♪ From the north of the Shetland Islands, we sail across an open stretch of water to the most northerly of all the British Isles -- Out Stack.

♪♪ ♪♪ This tiny, little rock lies on the same latitude as Southern Greenland.

And not many people know the British Isles extends this far north.

It lies between the North Sea and the Atlantic and is where two oceanic currents collide.

The strong upwellings push nutrients to the surface, making these waters some of the richest and most productive in the U.K. Gannets nest here on the dizzying sheer cliffs 27 meters high.

These rugged islands provide a haven for nature beyond the reach of mankind.

To our delight, a school of inquisitive Risso's dolphins swims alongside Pelican of London.

This pod includes some young calves.

They, too, are drawn to feed in these rich waters.

Inshore, the upwelling also provides a bonanza of fish for one of the island's most endearing creatures, the otter.

The Shetland Islands are home to over 1,000 individuals.

They were hunted by the Vikings for their fur pelts, which were traded locally and further afield.

[ Otter squeaking ] When the Vikings left, the otter population quickly recovered and have now reclaimed the islands for their own.

In the shallows, otters are top of the food chain.

But a larger predator stalks the deeper waters -- killer whales.

This pod has traveled hundreds of kilometers to reach the waters around the Shetland Islands.

The plentiful fish support thousands of gray seals, which are a favorite prey for hungry killer whales.

They flush out the hiding seal and, working as a team, enjoy the spoils.

Shetland is a wild frontier land and can be harsh and savage, as well as beautiful.

♪♪ ♪♪ From Out Stack, we travel to the Fair Isle, the most remote inhabited island of the British archipelago, lying halfway between Orkney and Shetland, where the Atlantic Ocean meets the North Sea.

♪♪ Just under 5 kilometers long and 2.4 kilometers wide, it has a natural harbor with two lighthouses on the north and south of the island.

Stevenson Lighthouse, in the south, is the tallest in the Shetland Islands.

Historically, the only way to reach Fair Isle was by crossing the rough seas.

Even today, the tiny island isn't shown on many maps, and there are just a few flights in and out each week.

Fair Isle is home to just 48 people and has only one shop, which doubles as a post office.

Yet, diverse industries and a proud culture thrives here.

[ Bleating ] Traditional knitwear has been created on the island for generations.

It was used in many of the Antarctic expeditions of the early 20th century and is considered among the very finest in the world.

These famed woolen knits are exported all over the globe, and each handmade jumper can cost thousands of pounds.

Eileen Thomson, one of the local residents, tells us what it's like living on such a small island with so few people.

-So, I'm very lucky to actually have Fair Isle in my blood.

I've got quite a full family tree that goes back until I think it's around the 1640s.

So it's an amazing thing to have such a strong connection.

Historically, this was the main route that a lot of the sailing ships took from Europe going to the New World.

The English Channel was too dangerous, too congested, so they all came around the north of Scotland.

I think we're very lucky that geographically where we are, we have quite good connections, we have good Wi-Fi, we have good mobile signals, which I know is a really, really important thing and majorly lacking for a lot of places.

-It seems there are better connections here than in many parts of mainland Britain.

-We're really lucky.

So, we have -- We're lucky to have a big repeater mast on the top of the island, because it's kind of like a stepping-stone between the mainland of Scotland to Orkney, to Fair Isle, up to Shetland.

You know, you can work from home.

You can do a call-center job working here.

So it really opens up the fact that if small places have good Wi-Fi, have good telecoms, you can work these jobs and still live here and enjoy the good things about being in a place like Fair Isle, be in a community.

So I think it's really important that people don't assume, because we're on a small island far away, that we're isolated.

In some ways, you have to be more open and more sociable here, because we have to make friends with our neighbors.

-You might think that the most remote inhabited British Isle would be a sleepy sort of place, but there is just so much energy here.

People seem to have two or three jobs.

They also run B&Bs.

They raise lambs.

There is so much creative energy.

The island is full of artists and manufacturers, along with the knitwear that's exported right the way around the globe.

This island may well be remote, but it's definitely not isolated.

It seems they have the best of both worlds.

[ Bleating ] ♪♪ ♪♪ From the Fair Isle, we travel to the Orkney Islands.

This archipelago of over 70 islands off the north coast of Scotland is home to some of the greatest Neolithic and Bronze Age settlements and archeological treasures unearthed in Europe.

On the west coast of the Orkney Islands is the Neolithic settlement of Skara Brae.

5,000 years ago, a community of farmers eked out a living in the harsh landscape.

They lived in Skara Brae for around 650 years before mysteriously abandoning it.

The settlement was forgotten for thousands of years, before it was rediscovered in 1850, when the site was uncovered during a great storm, revealing 10 stone structures around a circle.

Each circular house in the prehistoric village has the same design.

It's built of sandstone slabs covered with thatched roofs, with a fireplace in the center.

The villagers gathered around the fire during the long Orkney winters, using it to cook food and provide light and warmth.

8 kilometers away is the Ring of Brodgar, which dates back to the same time.

The ring is an impressive stone circle with 27 standing stones, some rising over 4 meters high above the wild moorland.

It's the largest Neolithic monument built in the area.

The ring has a diameter of 104 meters, and the site is thought to have originally contained 60 standing stones.

The exact purpose of the stones is unknown.

Some believe they were used as grave sites or to monitor the stars.

The Ring of Brodgar is the third-largest henge in the British Isles and was the epicenter of the stone-circle culture that spread across much of Britain.

♪♪ When the Vikings came to the Orkney Islands in the ninth century, they named the huge natural harbor enclosed within the island group Scapa Flow, which is Old Norse meaning "Bay of the Long Isthmus."

The harbor has a long maritime history and was home to a number of navies, providing shelter from the worst of the weather.

The deep-water harbor of the Orkney Islands occupied a key strategic location during the World Wars, as it was used to protect Britain's Royal Navy.

The islands became home to tens of thousands of personnel, and it was such an important base that it was heavily fortified with coastal gun batteries.

The batteries were equipped with guns from the United States and manned by the Royal Marines, as well as local men from the Orkney Royal Garrison Artillery.

Hoxa Battery was built during World War I with powerful 6-inch gun emplacements and magazines that guarded the southern entrance to the harbor.

Scapa Flow was so heavily fortified and so important to the Royal Navy that several of the inlets between the islands were cordoned off.

Blockships were deliberately scuttled to make barriers to prevent German ships or submarines from entering the harbor.

Some of the wrecks are still above water, a poignant reminder of the war.

After the German defeat in World War I, their fleet was interned in Scapa Flow under the terms of the armistice while negotiations took place.

The German admiral Ludwig von Reuter feared that the German ships would be seized by the British and used against Germany, so he ordered the German fleet to be scuttled and told the German sailors to abandon ship.

♪♪ 52 of the 74 German ships disappeared under the waves.

A salvage operation followed that managed to raise 45 of the 52 scuttled ships.

But seven still remain on the seabed to this day -- four German cruisers and three battleships.

We've chartered a dive boat to find out what happened to those ships.

Diving is now a popular pastime in Scapa Flow, and the war wrecks have become an international diving location, attracting divers from all over the world.

There are few places which offer such an abundance of large historic wrecks lying close together in shallow waters.

♪♪ The three battleships rest upside down on the seabed at a depth of 45 meters.

♪♪ ♪♪ When you swim next to the propellers, cannons, and guns that shaped history, you can see they are clearly recognizable as warships.

♪♪ ♪♪ The death of the warships has created new habitats.

The rusting wrecks have become a haven for marine life.

A century after they were scuttled, the iron hulls of the ships have become artificial reefs on the silty bottom.

They are now home to soft corals called dead-man's-fingers... starfish... and sea urchins.

Now the waters are peaceful again, and Scapa Flow at sunset belies its dramatic history.

But for our journey, it's the calm before the storm... as we're about to cross one of the most dangerous stretches of waters of the British Isles, a notorious strait that separates Orkney from the Scottish mainland.

These waters are known as the Pentland Firth.

It's a choke point where the tidal currents get concentrated, making really fast water speeds, really powerful currents, and tall waves.

Countless ships have gone down right here in these waters.

The waters can flow at over 30 kilometers per hour.

It's really dangerous for shipping.

It's like a giant funnel which squeezes currents between mainland Scotland and the Orkney Islands, creating massive waves that can batter ships.

But we'll need to cross the rough straits to continue our journey to our next destination -- the Hebrides.

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