Nothe Fort /noʊð/ is a fort in Weymouth, Dorset, England. The fort is situated at the end of the Nothe Peninsula, which juts eastwards from the town of Weymouth, and Weymouth Harbour, into the sea to the north of ex-military Portland Harbour. The fort is located next to Nothe Gardens. The coastal defence was built between 1860 and 1872 by 26 Company of the Royal Engineers to protect Portland's harbour, which was then becoming an important Royal Navy base. Shaped like the letter D, the fort's guns covered the approaches to both Portland and Weymouth harbours. The design included bomb proof casemates for cannons arranged around the circular sides, and deep magazines beneath the straight, landward side.