Strait of Tartary
Looking at the map, one could think that the Strait of Tartary would provide a convenient connection for boats sailing from the Sea of Japan to the Sea of Okhotsk, e.g. from Vanino to Magadan. However, according to the SASCO that operates that shipping line, their ships rarely travel that way. The usual winter route from Vanino to Magadan is via Tsugaru Strait, and around Hokkaido; the usual summer route, is via La Pérouse Strait and around Sakhalin. Only when coming back from Magadan to Vanino with a low load and in good weather would the ships travel along the shortest route, i.e., via the Amur Liman, Nevelskoy Strait, and the Strait of Tartary proper (which SASCO calls the "Strait of Sakhalin" – "Sakhalinsky Proliv").