The first structure on the site of Old Bümpliz Castle was a Burgundian royal estate which was built around 900. Around 1250-1270 a round stone tower was built in the center of the site. This round tower was quite unusual for Bernese castles but may indicate a savoyard influence. Since Peter II of Savoy held authority over Bern at the time, it is likely, but not confirmed, that the round tower was built as a symbol of Savoy's power. The round tower no longer exists, but its location is marked with a cross on the floor of the current restaurant terrace. Shortly after the construction of the tower, the wooden wall was replaced with a stone wall and a half-round tower was added to protect the wall. The round central tower was demolished in the following decades. The growing Bernese power began to force Savoy out of Bümpliz and by the late 13th century, there were Bernese nobles who were naming themselves after their estates in Bümpliz. Under the Bernese nobles, the castle remained unchanged until 1470.
In 1470 Bümpliz village and the castle became part of the lands of the powerful Bernese patrician Erlach family. The castle was rebuilt from a purely defensive structure into an impressive administrative and residential castle. A new gatehouse tower was built, and stands, almost unchanged, today. The supports and structure of the drawbridge over the moat are still visible today.
In the following century, the Old Castle became increasingly old fashioned and uncomfortable. In 1742, Daniel Tschiffely hired Albrecht Stürler to replace the old building with the Neues Schloss Bümpliz. The New Castle was built southwest of the Old Castle. During construction, much of the Old Castle was pulled down or rebuilt.
In 1839 Johann Friedrich Albrecht Tribolet bought the Old and New Castles from Carl von Tavel. He rebuilt the buildings and used them as a private sanatorium for mental patients.
In 1979/80 the Castle was rebuilt. The gate was reopened in the gatehouse, a portion of the moat was excavated and a drawbridge added. The windows were rebuilt in the baroque style and the burned roof was rebuilt as close to original as possible. The north-west wing was rebuilt, while the north-east wing was recreated in concrete and glass. A restaurant opened in the north-east wing, the gatehouse and the courtyard. The rest of the building was converted into the Bümpliz village archives and into meeting rooms or offices.
References:Towering 52 meters above the sea, Bengtskär lighthouse is the tallest one in Scandinavia. The building started in in 1905 after the shipwreck of S/S Helsingfors and was completed in 1906. The lighthouse was designed by architect Florentin Granholm. On December a special petrol lantern, designed and built in Paris, was brought to Bengtskär and installed atop the tower.
German fleet bombarded Bengstkär in the First World War in 1914. Since the Gulf of Finland was heavily mined, it was not until 1919 that the surrounding seas were declared safe for shipping, that the light was lit again.
After the war the military value of Bengtskär increased as part of the defence system of independent Finland. In Second World War (1941) Soviet Union made a suprise attack to island. After a bloody battle, the small Finnish garrison emerged victorious. Intermittent repairs to the facility continued during the post-war period.