Trelew (Spanish pronunciation: [treˈleu], from Welsh:tre "town" and the name of the founder) is a city in the Chubut Province of Argentina. Located in Patagonia, the city is the largest and most populous in the low valley of the Chubut River, with an estimated 100,000 inhabitants as of 2010. The Trelew municipality is part of the Rawson Department, whose capital, Rawson, is also the provincial capital.