Trelew is a city in Chubut, Argentina.
South towards Comodoro Rivadavia
One of the "28 de Julio" buses to Rawson passes by the interchange for the Ruta 3. As of January 2015, it costs 6.40 pesos (~ $.50 US). When you get on, tell the driver you're heading to Comodoro Rivadavia, and you can get out at the interchange. From there, walk about 100m, and there's a service station.