Taxis in El Salvador are yellow, painted with black numbers and a "taxi" sign. They can be hailed anywhere on the street - in fact, they usually see you and honk before you see them - and also tend to congregate in the main square and around bus stations in towns and cities. Fares should be agreed before you set off (be prepared to bargain). Expect to pay US$2-5 for most city trips, and anything upwards of US$30 for a half-day driving around the countryside (a good way to see some of the remoter spots if you're in a hurry). Tipping is not usual unless you've rented the taxi for the day.