The southernmost point is the islands of Southern Thule, though they are sometimes thought of part of Antarctica. The mainland of the Americas is the world’s longest north-to-south landmass. The distance between its two polar extremities, Murchison Promontory on the Boothia Peninsula in northern Canada and Cape Froward in Chilean Patagonia, is roughly 14,000 km . The mainland’s most westerly point is the end of the Seward Peninsula in Alaska; Attu Island, further off the Alaskan coast to the west, is taken into account the westernmost level of the Americas.
