Suomenlinna is a must-see for any visitor to Helsinki. The ferry to this island fortress is simple…read moreto locate at the main pier, and it runs reliably on its 20-minute schedule, late into the night, so returning is easy as well. There's something for everyone to enjoy along Suomenlinna's scenic walkways, whether you're a history buff or casual tourist, with many vista walks and building sites to explore. Take your camera, enjoy a meal there, and check out the shops too (I particularly loved the gorgeous photo/narrative book by local Tim Bird, available in the main gift shop). Suomenlinna is simply an exceptional UNESCO heritage site!