South Weeks, also known as Mount Weeks-South Peak, is a mountain in the Pliny Range of New Hampshire’s White Mountains in western Berlin, situated between Mount Weeks and Mount Waumbek. It was named for John W. Weeks, the New Hampshire-born U.S. senator from nearby Lancaster, whose sponsorship of the Weeks Act of 1911 helped bring about the White Mountain National Forest and tied him closely to the region’s conservation history. The mountain lies in the upper Connecticut River watershed, with runoff from its southeast side flowing to Keenan Brook and the Upper Ammonoosuc River, and water from its north and west sides reaching the Israel River by way of Garland and Stalbird brooks.