Helsinki is famous for its cathedrals. Right next to the harbour, with a commanding position on a hill, is the Russian Orthodox (Uspenski) cathedral . We found the setting rather grander than the cathedral itself, which can also be said of Helsinki's other main attraction - the Lutheran cathedral (Tuomiokirkko). This huge white building is located two streets from the harbour and is often ringed by tourist coaches.
In our view, the true gem is rather further away on the other side of town. The Temppeliaukio kirkko is an architectural masterpiece. Almost invisible from the outside, this is built into the actual granite on which the city sits, so it is almost underground, but the light streaming through the copper roof creates the most wonderful effect. If you want to get married, this is THE romantic place to get hitched.
The other major attraction is the fortress of Suomenlinna, on an island (actually five islands) at the entrance to Helsinki harbour.They claim you can easily spend a day here. Ferries leave regularly from the Esplanade, or you can moor in the marina on the island itself - although it tends to be busy.