It was often considered the only safe way to move between the Atlantic and Pacific Oceans, as the Drake Passage separating Cape Horn from Antarctica is notorious for turbulent and unpredictable weather, and is frequented by icebergs and sea ice. Ships in the strait, protected by Tierra del Fuego to the south and the coast of continental South America to the north, crossed with relative ease, and Punta Arenas became a primary refueling port that provided coal for steamships in transit. Sailing ships, partly because of variable winds and currents in the strait, generally preferred the Drake Passage, where they had more room to maneuver.[citation needed]