Minnesota-born novelist and satirist Sinclair Lewis once wrote, “Winter is not a season, it’s an occupation.” If winter is an occupation, then snow would be its fortification. While the frozen stuff in all its forms (icy, fluffy, sticky, slippery) can bring joy to some, like skiers and children, for many it presents an obstacle that needs to be navigated and cleared. From prehistoric skis to modern-day plows, see how humans have interacted—and dealt—with snow through the ages.