Ruotsinsalmi fortress was built by Russians in 1790-1796. It was part of the South-Eastern Finland fortification system which was planned to defence St. Petersburg. The sea fortress was located to islands in front of the city of Kotka and Kyminlinna fortress. It contained three main strongholds (Fort Katarina, Fort Elisabeth and Fort Slava) and several redoubts and artillery batteries.
Ruotsinsalmi fortress lost its original defensive value only couple of years later, when rest areas of Finland were joined to Russia after the Finnish War (1808-1809). It was disbanded in the 1830's and during the Crimean war (1855) Anglo-French fleet destroyed the empty fortress permanently.
Today individual remnants of fortresses can still be found for instance beside Catherine’s path and on the island of Tiutinen. Also Fort Elisabeth's embankments have been renovated in recent years. The island is easily accessible by regular boat services in the summer.
Sweetheart Abbey was a Cistercian monastery, founded in 1275 by Dervorguilla of Galloway in memory of her husband John de Balliol. His embalmed heart, in a casket of ivory and silver, was buried alongside her when she died; the monks at the Abbey then renamed the Abbey in tribute to her. Their son, also John, became king of Scotland but his reign was tragic and short. The depredations suffered by the Abbey in subsequent periods, have caused both the graves to be lost. The abbey, built in deep-red, local sandstone, was founded as a daughter house to Dundrennan Abbey; this Novum Monasterium (New Monastery), became known as the New Abbey.
The immediate abbey precincts extended to 120,000 m2 and sections of the surrounding wall can still be seen today. The Cistercian order, also known as the White Monks because of the white habit, over which they wore a black scapular or apron, built many great abbeys after their establishment around 1100. Like many of their abbeys, the New Abbey's interests lay not only in prayer and contemplation but in the farming and commercial activity of the area, making it the centre of local life. The abbey ruins dominate the skyline today and one can only imagine how it and the monks would have dominated early medieval life as farmers, agriculturalists, horse and cattle breeders. Surrounded by rich and fertile grazing and arable land, they became increasingly expert and systematic in their farming and breeding methods. Like all Cistercian abbeys, they made their mark, not only on the religious life of the district but on the ways of local farmers and influenced agriculture in the surrounding areas.
The village which stands next to the ruins today, is now known as New Abbey. At the other end of the main street is Monksmill, a corn mill. Although the present buildings date from the late eighteenth century, there was an earlier mill built by and for the monks of the abbey which serviced the surrounding farms.