Soderskär Lighthouse stands on a small bare island in the Gulf of Finland, about 20 km south of Porvoo. The octagonal red-brick tower is one of the oldest surviving lighthouses in Finland, built in 1862, and the surrounding archipelago is a nature reserve famous for its seal colonies. On a summer day the island attracts boaters, birdwatchers, and anyone who wants to experience the extreme openness of the Finnish outer archipelago.
Excursion boats run from Porvoo and the surrounding archipelago in summer, typically taking two to three hours each way. The lighthouse exterior and the surrounding rocks — often dotted with grey seals — make the trip worthwhile.