The Boh, falsely named the Southern Bug, is a real plateau river. It rises in the village of Kupil, near the source of the Sbruch, on the Austrian border, and flows as a typical Podolian mud-streamlet, in a flat valley, covered with ponds and swamps. But, beginning at Mezibiz, its bed becomes rocky, the valley slopes become high and keep approaching each other. The Boh Valley gradually becomes a cañon-like “yar,” altho it is at no point so deep as the Dniester Valley. The granite-gneiss formations of the Ukrainian horst appear here as picturesque shore rocks and slopes along the river and form innumerable rapids (as, for example, Constantinivka) in the river bed. Stony beds and narrow, rocky valleys are also found in the most important tributaries of the Boh—the Sob, Siniukha, Inhul on the left; the Kodima and Chichiclea on the right. All of them have little water, and in dry summers only a chain of ponds marks the valley road of the river. The main stream, too, has not much water, being unfit for navigation even in the time of the spring floods. Only the last 130 kilometers of its course, from Vosnesensk down, are navigable. At the entrance of the Inhul the Boh begins to widen considerably, the current becomes slow, and the depth at Mikolaiv sufficiently great to enable smaller sea vessels to reach its harbor. Slowly widening, the river gradually turns into the Buh liman, which has the winding outline of a river and unites with the great liman of the Dnieper. The entire length of the Boh is over 750 kilometers.