The Romanesque style Elne Cathedral was consecrated in 1069. In 1285, during the Aragonese Crusade, French troops sacked the town and massacred the townspeople who had taken refuge in the cathedral.
Work began on rebuilding the cathedral in the 14th century but was never finished, which explains the irregular appearance of the main facade - the tower on the right was built at this time but not the tower on the left, so a much smaller tower was added later instead. The cathedral is notable for the lack of decorative stonework on the outside.
The cloisters were also built over the course of three hundred years, which explains why some parts are more ornamented than others - despite this the closters are very beautiful, with marble arches featuring interesting capital stones surrounding a nicely maintained garden. The cloisters now also contain a Museum of History and a Museum of Archaeology.
References: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.