A defensive brick building in Jarocin, defined in a 1496 document as a fortalitium, had presumably already been erected by the beginning of the 15th century. This building was then rebuilt, extended and eventually demolished. The building known locally as skarbczyk (the jewel box) is all that remains of it today. A lot of decorative fragments of Gothic furnace tiles, attesting a once opulent castle interior, have been uncovered here during the course of excavation work.
There is a two-storey brick and plaster building laid out on a rectangular plan and surrounded by what used to be moats by the pond in the southern part of the park. The domed turret adjoining the body of the building from the west was added a good while later. The main body has a tiled pitched roof. The walls are supported by strong corner abutments and framed rectangular window openings. A stone bas-relief of the Leszczyc coat of arms of the Radoliński family hangs above the portal on the tower elevation. The vaulted rooms inside have been preserved.
It is now the Jarocin branch of the Regional Museum.
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.