Radzyn Chelminski, Poland
13th century
Dobczyce, Poland
1311
Łagów, Poland
c. 1299
Nowy Sącz, Poland
1350
Warsaw, Poland
1834
Kliczków, Poland
1297
Toszek, Poland
c. 1222
Otmuchów, Poland
1159
Bytów, Poland
1398-1405
Odrzykoń, Poland
14th century
Żywiec, Poland
15th century
Ciechanów, Poland
14th century
Gdańsk, Poland
1482
Korzkiew, Poland
1325
Kłodzko, Poland
c. 1300
Uniejów, Poland
1360-1365
Tykocin, Poland
1433
Gola, Poland
1580
Srebrna Góra, Poland
1765–1777
Sanok, Poland
14th century
Bomarsund fortress and garrison was built in 1832-1854 by Russian Empire to defence Åland Islands against enemies. British and French fleet attacked against it during the Crimean War in 1854. After a week of fighting the British stormed the remaining fort. Anglo-French forces destroyed it totally after battle. In the Treaty of Paris 1856, the entire Åland Islands were demilitarized, which is a status that has been preserved until this day.
Nowadays there are some ruins left and fortress area is open for visitors.