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Bulverket today

Sweden · Ruin

Bulverket

The Bulverket is the remains of a large 12th-century wooden fortification built in the middle of Lake Tingstäde on Gotland. At its prime it was a square wooden platform on timber caissons, ringed by concentric palisades, with houses and mooring landings; its exact purpose is unknown. Archaeological work has mapped the submerged timbers and recovered boat fragments used to reconstruct a Viking-style craft.

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Photograph via Wikimedia Commons

Its prime

1135

Today

Ruin

As it stood in 1135

What Bulverket looked like in its prime.

A vast square wooden platform formed by four broad piers on tall square log caissons, each pier about 30–40 m wide and the platform sides ~170 m long, enclosing a central open basin of water. Two concentric circular palisades of vertical timber piles surround the platform, the outer palisade standing up to 50 m from the platform and the whole construction about 250 m in diameter. On the platform sit rows of small 3 × 3 m log and post‑and‑plank houses with low wooden roofs, decks about 1 m above the water, and central boat landings where clinker boats are moored.

Its story

The story of Bulverket.

The Bulverket is the remains of a large wooden fortification built in the middle of Lake Tingstäde on Gotland, a platform with houses on timber caissons, surrounded by a double palisade, the whole construction some 250 metres in diameter, with mooring landings. A 1989 archaeological survey dated its building to the 1130s and suggests it may have been used for less than a century.

Its original purpose is unknown: theories suggest a shelter during the turbulent times on Gotland at the end of the Viking Age, or the site of a last stand. Archaeological work has mapped the submerged timbers and recovered the remains of three boats; one served as the model for the Krampmacken, a Viking boat reconstructed in 1980 that has since made several journeys along old Viking waterways through Eastern Europe.

Step inside

8 places to explore in 1135.

The record describes 8 distinct spots at Bulverket, including 1 interior: interior of a typical platform house. Create your own photoreal reconstruction and explore every one, more scenes means more rooms, more angles, and more of the place to stand in.

Approach from the lake toward the BulverketOutside the outer palisade looking inNorthwest entrance through the palisadeEdge of the platform above a square caissonCentral basin and boat landingsBetween the houses on the platformInterior of a typical platform houseHigh vantage over the square platform and palisades

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Questions about Bulverket

What is the history of Bulverket?

Bulverket was built in the 12th century, probably in the 1130s, as a large wooden fortification in Lake Tingstäde. It may have served as a refuge during conflict on Gotland or as the site of a last stand. The structure may have been used for less than a century before collapsing, leaving submerged timbers and boat remains.

Why was Bulverket built, and what was it used for?

Bulverket was built as a heavily fortified refuge, although its exact purpose remains unknown. Theories include shelter during conflict, a last stand, a central trading and storage hub, or a place for fishing and storing goods. Its location in the middle of the lake made it difficult to access.

Where is Bulverket?

Bulverket is in Lake Tingstäde on Gotland, within Region Gotland. The remains lie in the lake rather than in a settled town, and the construction was raised in its least accessible part. Its setting is a central part of the site’s defensive design.

When was Bulverket built?

Bulverket was built in the 12th century, specifically in the 1130s. A 1989 archaeological survey dated its construction to that decade, while later examinations also place it around the beginning of the 1130s. The site may have been built in a relatively short period, perhaps no less than a year.

What did Bulverket look like in its prime?

In its prime, Bulverket was a square wooden platform about 170 metres along each side, supported by four broad piers on tall square log caissons. Two concentric palisades surrounded it, extending the whole construction to about 250 metres in diameter. Rows of small wooden houses stood above the water around a central basin with boat landings.

Is Bulverket still standing, or is it a ruin?

Bulverket is a ruin rather than a standing fortification. It has collapsed, and its logs are scattered across about 40,000 square metres on the lakebed. Natural sedimentation has preserved the submerged remains, including timbers, house parts and boat fragments, in very good condition.

Can you visit Bulverket?

Bulverket can be viewed by the public from the lake, including through clear winter ice or from a boat in summer. The remains lie underwater, so the main features seen are the submerged timbers, platform structures and palisades. A small electric boat with a glass bottom is available for viewing the site through the hull.

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