Passage: 1533-47: some 20 large raids on the frontiers.:71 1541: Crimean Khan crosses the Oka river on rafts under covering fire from Turkish guns.:12 1555,1562,1664,1565 The Khan lead a large army into Muscovy.:16.
How many years passed by during the 20 large raids? How many years were there raids on the frontiers? What did they use to cross the river? Which Khan crossed the Oka river on rafts under covering fire from Turkish guns in 1541? Which city did the Khan invade? Who's guns were shooting at the Crimean's?