The island of Märket
Märket (it 'marks' in Swedish) is a small uninhabited islet of the Baltic Sea, placed between Sweden and Finland, whose sovereignty she is divided between these two states. The Treaty of Fredrikshamn (Hamina) of 1809 defined the border between Sweden and the ancient Russian Empire and made to spend the frontier line for the center of the island.
The island measures approximately 350 m long for 150 wide one and has a surface of little more than 3 hectares.
There is a lighthouse in the Finnish part of the territory, which functioning was automated in 1979. When it was constructed for Russian and Finnish in 1885 there were no detailed maps of the island and after finished the work, they realized that they had constructed it in the Swedish area.
To arrange it it happened to them to modify the frontier line, so that the lighthouse was falling down of the Finnish side, but with two conditions: the entire surface of territory of each of the states could not change and neither could be modified the length of the line of the coast, in order not to interfere in the fishing rights of every country.
This problem gave place to an ingenious geometric solution with a frontier line in such a way that it can turn in the map.
Every 25 years the border is inspected by agents of both countries. The last time was in August, 2006. In addition to in ship, also it can go over to the island in helicopter.
As we can see in the photos that there have raised to Flickr few travelers who have approached over there, it is a question of a place with very attractive natural sceneries. There are seals and diverse classes of sea birds. Now it runs the risk of turning into tourist place.
Photos of Taivasalla: Gallery
More information detailed in the Spanish Wikipedia.