Bering Strait, at 1 The Lena at Verkholensk is navigable for 170 days, at Yakutsk for 153 days: the Yenisei at Krasnoyarsk for 196 days.
Are not uncommon at Krasnoyarsk, Irkutsk and Nerchinsk; even in the warmer southern regions of West Siberia and of the Amur the average winter temperature is 2.4° F.
And - 90° respectively; the minimum at Krasnoyarsk is - 67° F., at Irkutsk - 51°, at Omsk - 56°, and at Tobolsk - 58°58° F.
Although very heavy falls of snow take place in the alpine tracts - especially about Lake Baikal - on the other side, in the steppe regions of the Altai and Transbaikalia and in the neighbourhood of Krasnoyarsk, the amount of snow is so small that travellers use wheeled vehicles, and cattle are able to find food in the steppe.
The summer isotherm of 68° F., which in Europe passes through Cracow and Kaluga, traverses Omsk, Krasnoyarsk and Irkutsk, whence it turns north to Yakutsk, and then south again to Vladivostok.