Lake Onega of Petrozavodsk–Kizhi, Petrozavodsk–Velikaya Guba and Petrozavodsk–Shala. They are run by hydrofoil and motor ships and are used for passenger transport as well. In addition, passenger ships go on the route Petrozavodsk – Shala. Sailing is a popular activity on the lake and there is a sailing club in Petrozavodsk. Since 1972, every year at the end of July the lake has hosted the largest regatta in Russia ("") which is the Russian Open Championship in the Russian class of Cruisers Yachts "Open800". The regatta has international status. The largest city on the lake is Petrozavodsk – the capital of Republic
Lake Onega months. The highest water level is in June–August and the lowest is in March–April. Rivers bring of water per year to the lake, that is up to 74% of the water balance; the rest is provided by precipitation. Most of the lake water (84% or per year) outflows via a single River Svir, and the remaining 16% evaporates from the lake surface. There are frequent storms more characteristic of a sea than a lake; waves of are not uncommon and may even reach . The lake freezes near the coast and bays in late November and December and around mid-January