In 2009, designer Aino-Maija Metsola heard that one of the highly coveted artists’ studios at Suomenlinna, a former military stronghold located in the Finland Strait, was available to rent. She immediately applied. “It’s great luck if you get one,” recalls Metsola, who beat out many other applicants and now lives on the island with her husband, graphic designer Georgi Eremenko, and their dog, Turo. The apartment is one big open space with thick walls, high ceilings, and a view of the sea. Their neighbors are all creative types, including a movie director, a costume designer, and a painter. “We have a lot of parties; it’s a really nice environment,” explains Metsola, an in house designer at Marimekko, whose recent line for the company, the Weather Diary, is inspired by her…