Trelew (Welsh: Tre Lew(is)) is a city in the province of Chubut, in Argentine 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.
It is an important commercial and industrial centre for the region and is the main hub for wool processing, accounting for the 90% of the activity on Argentina. The produce of this industry is mainly shipped and exported through Puerto Madryn and Puerto Deseado.
Trelew is home to the Museum of Paleontology Egidio Feruglio, showcasing the paleontological heritage of the Patagonic region, and considered one of the most important of its kind in South America and the Astronomic and Planetary Observatory.
The city is served by the Almirante Marcos A. Zar Airport, of both civilian and military use. The airport's runway is shared with the Almirante Zar Naval Base, home of the Lockheed P-3 Orion squadron of the Argentine Naval Aviation.
The city was founded in 1886 by Welsh settlers, hence its name of Welsh origin, feature shared with many other cities and towns in the area