Hakoinen Castle was an ancient hill fortification, but nowadays there's only some ruins left. Dated medieval, the fortification was situated on a very steep rock by lake Kernaala (Kernaalanjärvi) reminiscent of a hill fort tradition. The top of the rock is 63 meters above the water level in the lake. Today very little remains of the castle. Equally little is known about its origins. One postulation is that it was built by the Swedes as their original stronghold in the medieval Häme area.
The castle was probably built at the end of the 13th century or during the early 14th century. It has been speculated that Hakoinen might have been the fort that was attacked by invading Novgorodian forces in 1311 during the Swedish-Novgorodian Wars, as described in the Novgorod Chronicle.
Eventually Hakoinen was left out of use. Some activity seems to have remained there until 1380s. The castle rock was later a part of a large estate belonging to the bailiff of Häme Castle. According to excavations, the castle was divided into two parts. Lower defensive constructions were mostly made of wood. Constructions on the rock were made of bricks and rocks. The castle probably had one tower.
Although very little remains of the castle, the medieval flora and huge sights from the top of the hill makes Hakoinen castle hill interesting place to visit.
References:The Clementinum is a historic complex of buildings in Prague. Until recently the complex hosted the National, University and Technical libraries, the City Library also being located nearby on Mariánské Náměstí. The Technical library and the Municipal library have moved to the Prague National Technical Library at Technická 6 since 2009. It is currently in use as the National Library of the Czech Republic.
Its history dates from the existence of a chapel dedicated to Saint Clement in the 11th century. A Dominican monastery was founded in the medieval period, which was transformed in 1556 to a Jesuit college. In 1622 the Jesuits transferred the library of Charles University to the Klementinum, and the college was merged with the University in 1654. The Jesuits remained until 1773, when the Klementinum was established as an observatory, library, and university by the Empress Maria Theresa of Austria.