From the end of the Time of Troubles small groups of Russians penetrated and colonized the Far Eastern Arctic, in two distinct waves originating from White Sea area and from the Ural Mountains. In 1639 the company of Postnik Ivanov, a Siberian cossack, reached the site of Zashiversk and stayed there for the winter. The site, located below the rapids ("Shivery", шиверы, in Siberian dialect, thus the name "Zashiversk") of the Indigirka River, some 870 kilometers from its inlet, marked the crossroads of a river route to Kolyma and Chukotka and a land route ("Tsar's Trail", царская дорога) from Yakutsk to Nizhnekolymsk. Postnik reported abundance of valuable sable and fish, significant population of native settlers and nomads as well as silver possessed by the Yukagirs; the voyevoda of Yakutsk responded with establishment of a permanent colony to exploit the opportunity.