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Photo of Ole Crumlin-Pedersen Viking Ships -- Ole Crumlin-Pedersen

For nearly three centuries, the Vikings ruled the seas in sleek, streamlined vessels. Now, reconstructions of ancient ships reveal the technological innovations of Viking sailors. Discover more by reading answers to viewer's questions from Ole Crumlin-Pedersen at the Viking Ship Museum.

Q How long does it take to recreate a Viking ship, and how much does it cost?

The replicas we have built in Roskilde for research purposes (Helge Ask and Roar Ege) have taken between 12 and 30 months from start of the project to launching. The length of the period does certainly not indicate the time needed by the original builders in the 11th century as they were much more trained and did not have to stop on the way for analysis of the archaeological evidence to choose the right tools and building procedures. Originally an average Viking ship could probably be constructed in 6 to 9 months time.

The cost of building a medium size Viking ship to the high standards set by us is approximately $500,000. This price includes some elements of documentation and research, as well as some time spent on presenting the building project to the visitors of the Viking Ship Museum.

Q What is the minimum number of Vikings needed to sail a longboat? And what is the maximum number of sailors/passengers a longboat could hold on a trans-Atlantic crossing?

The longships were primarily warships, manned in the outset with a maximum of warriors, also acting as rowers. After a defeat in battle the ship might still be handled by a crew numbering a third or a quarter of the original number. In the 17m-long Skuldelev 5-replica Helge Ask, shown in Nordic Sagas with Alan Alda rowing, the full crew is 26 rowers (13 each side), a steersman and a look-out, a total of 28 men. In longer ships the number of men would increase by two for each additional meter, as the average spacing of the oars was one meter or slightly less. The largest Viking longships were probably manned by as many as approximately. 80 men. In broad ships like the Norwegian Gokstad ship there would be room for several more men than the number of oarsmen. This was also the case for the broad and deep cargoships. They could be sailed by a crew of only 4 to 5 men, but they could transport a much larger number of persons if needed, for instance for the transfer of settlers from Norway to Iceland. In the large knorr-ships for trans-Atlantic crossings they may have found room for 30-40 persons with their personal belongings and some cargo.

Q How do you know what tools the Vikings used?

There are three sources of information about the tools used in Viking shipbuilding: 1: actual tools from the period found in graves or bogs or in excavations at settlements; 2: tool-marks on the timbers of the ships showing the type of tool, typically axes, used for the final dressing of the surface of the building elements; and 3: traditional tools used in areas, such as western Norway, where the technology in boat building has remained largely unchanged over the centuries.

Q On the show, we were told that a new ship was being excavated outside the museum. What have you found out about this new vessel?

On the show there were shots from two different ships that were under excavation in Roskilde in the autumn 1997: a 14th century ship, a small cargoship, excavated by divers in the Museum Harbour; and an 11th century Viking longship, originally approximately 35 m long and thus the longest longship ever found, excavated on a dry-land site on the Museum Island. These ships are now being recorded in detail and conserved for future display in the Viking Ship Museum.

Not only these two ships but a total of nine (!) medieval ships were found at the construction of the Museum Harbour for the Viking Ship Museum -- a most remarkable situation for a museum to find its sources on its own building plot! The ships had sunk on various occasions, as they were riding at anchor in the open harbour bay, exposed to northerly storms. Three years ago the same happened for the replica Helge Ask which was only salvaged because we could send out divers on the rescue operation.

Q My science class and I would like to know if you ever found any gold or bones or anything like that when you excavated the Viking ships.

No gold or human bones were found with the Viking ships I have excavated, as they were scuttled to be used to block the way for enemy ships (the Skuldelev ships exhibited in Roskilde) or used as a fireship on an attack on the Viking town of Hedeby (the Hedeby ship exhibited in Schleswig). In both these cases the ships were taken out of their normal use before their secondary use. The newly found Roskilde ships were sunk by storm when riding at anchor in shallow water and they were emptied of their contents either before or after wrecking. The royal graves with Viking ships (found at Gokstad, Oseberg, Ladby and a few other places and excavated several years ago) originally contained several treasures, but they have all been disturbed in antiquity so that only scattered traces of the treasures remained to be excavated.

In 1976 a 16-year old Danish boy located an old wreck at Vejby Strand north of Copenhagen when snorkeling at shallow water. He reported the find to the National Museum after finding gold coins in the ship, and I directed the excavation and raising of the wreck which turned out to be the bottom part of a cargoship wrecked on the open coast around 1375 AD. With this ship were found 110 gold coins, 86 of which were found by the boy who got an award for the find, while I found the greater part of the remaining number of coins. This case is an exception, however, for medieval or earlier ships, as gold is only very seldom found with these, and the same is the case for human bones.

Q I noticed that the sails on the Viking ship you were sailing looked rather old. Is this decorative, a characteristic of the material used -- or maybe just that the sails are just "well used"?

The color of the sails is authentic. In the Viking Age the sails were made of wool from long-haired sheep, and we have found a small stock of sheep of Viking-Age character on a small Norwegian island to provide us with materials for woolen sails. These are darker in color than modern sails, and besides they are treated with a mixture of horse-fat and ochre to be airtight and water-repellent in the texture. For prestigious ships wool of different colors may be used to give sails with stripes of different colors.

Q I am doing a report on Vikings and their ships. I would like to include what YOU think is an interesting fact about Vikings or Viking ships.

I think the Vikings are interesting to study because they lived at a time when things changed rapidly in Scandinavia -- from a belief in the old Nordic gods to Christianity, from a de-centralized organization in chiefdoms to a unification into the kingdoms of Norway, Sweden and Denmark as they still exist. During the Viking Age the first towns were built in Scandinavia, and Vikings from the Scandinavian kingdoms traveled more widely than any other Europeans at the time, from the White Sea in the North to the Black Sea in the South, from Russia in the East to Vinland in the West.

Their ships are especially fascinating because they were built to a superb standard with a high prestige value and a refined technology from which we may even learn something today in designing modern yachts.

Q Did the Vikings have a written language? If so, do we have any written accounts of their life, boat building, etc.

The Vikings had a written language, and they carved their runic inscriptions into wood or stone to commemorate their dead. There are only few of these inscriptions preserved, however, and they are not very informative in general. The runic alphabet of the Viking Age, the 'futhark', consisted of 16 letters which were designed to be easy to carve in wood.

Q Do you think it is possible that there are any Viking ships in North America waiting to be discovered? If so, where do you think they would be?

It might be possible to find wrecks of Viking or medieval Norse ships in North America, just as we have recently been able to identify parts of a wreck from Belgium as of Viking origin. The shipwreck site would then be in an environment with quick sedimentation to avoid the wood being eaten away by shipworm or soft-rot. In order to be found the sediments should be eroded away or dredged away and the wreck should be noticed by someone aware of its importance, reporting the find to an archaeologist ready to go in action right away. If just one of these several factors fails the chance is missed. In Denmark most people are interested in ancient ships and archaeology in general and they are very observant and reporting to a dense network of archaeological museums - therefore we have a high number of finds of Viking and medieval ships in Denmark!

Q What kind of wood were the ships were made of? Were nails used? Did they use patterns or build from memory? How did the Vikings became such expert ship builders?

Viking shipbuilders preferred to build their ships from oakwood in southern Scandinavia and from pine in northern Scandinavia. Other species of wood were also used, however, for special purposes, such as ashwood for the upper planks in the longships (this is probably why the English written sources refer to the Vikings as 'ashmen'). In areas with a strong shipbuilding activity such as around the Viking town of Hedeby they ran out of stock of the high-quality oak needed for the ships in the 10th to 11th centuries and had to use a number of other species of wood as well.

The planking was assembled with iron rivets (the Slaws used small wooden dowels) in lapstrake/clinker fashion, creating the lines of the hull by varying the shape of the planks and the angle from one plank to the next. Adjustments could be made with studs from the ground to the outside of the planking and stones placed inside the ship. After the bottom part had been built up with the planking (without any drawings or molds, just with the aid of a well trained eyesight) the bottomframes were cut to shape and inserted, and the sequence could be repeated with the sides of the ship.

Every Viking male could use an ax, not only as a warrior but mainly for many jobs in everyday life, such as building houses or ships. The main responsibility in shipbuilding, however, rested with the 'stem-smith', the master shipbuilder who knew the secrets of the trade (probably some sophisticated 'rules-of-thumb' based on measurements in proportion to the length of the keel). His ships would be measured against the standard of other ships of the time, and there was a strong competition and a lot of pride put into the ships, rather than business-like considerations.

Q What is the longest distance a Viking ship ever traveled?

The longest voyage ever by a Viking ship was around the World! The Skuldelev 1 replica 'Saga Siglar' in 1984-86 circumnavigated the globe (with an auxiliary engine and by way of the Panama and Suez Canals). In spite of the engine, mainly used for maneuvers around harbours, this was a striking example of the seaworthiness of the 'knorr' type of ship, thought to be of the kind used by the Vikings on the North Atlantic.

In the Viking Age Viking ships sailed from the White Sea in the North to the Mediterranean and the Black Sea in the South, from the Russian rivers in the East to the coast of North America in the West. Of course it was not the same shiptypes that sailed the Atlantic and the Russian rivers but by now we know enough about the different types of vessels to give an impression of the types for each of these routes.

Q We want to know more about the Vikings' food, language, religion, clothes, wood carvings, writings and culture. Can you please suggest some websites or other sources to find more information about the Vikings?

As I am an old man (aged 62) I prefer to find information to questions regarding the Vikings in general on my bookshelves or in the libraries, and you will find many useful books on Vikings in the public libraries. But you may also take advantage of the great 'library' offered by the www. Try some of these websites: The World of the Vikings
This site calls itself the definitive guide to Viking resources on the internet and features links to museums, re-enactments, schools, sagas, ships and more.

Leif Ericson Vikingship
Visit a group whose mission is educating North Americans about Leif Ericson, the first European known to have discovered this continent in 1003 AD. Learn about the group's Viking ship, the Norseman, order a kit to build one and find out about re-enactments and other events, plus links to many Viking-related sites.


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