Kuressaare castle
The Danes modernized the defence systems of the castle. The work
began in about 1600 and lasted till 1640. Using the old belt of walls, they erected a mighty
system of earthwork with bastions and encircled it with a 30 m wide moat, filled with
seawater.
On the ground of Brömsebro peace treaty in 1645 Sweden took possession of Saaremaa.
On September 15, 1710 the Swedish garrison, ravished by the plague, surrendered to the
Russian army with no resistance.
After Russia founded Bomarsund castle on just-occupied land islands and in the vicinity
of the Swedish capital, Kuressaare was once and for all excluded from the list of the
fortifications of the Tsarist Russia in 1836. A year before the castle had been sold to the
Knighthood of Saaremaa for 3,000 roubles
During 1904-1912 the convent building was renovated by architects W. Neumann and
H.Seuberlich. The two upper floors of the Defence Tower were constructed anew; the
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