Mérida sits on the A-5 motorway between Madrid and the Portuguese border, about three hours from each. By car, it is an easy stop on any drive west from Madrid to Lisbon or south to Seville (two and a half hours, mainly on the A-66). Driving and parking in Mérida itself are easy by Spanish standards: free public lots ring the old town, and most of the historic centre is pedestrianised.
Trains from Madrid (Atocha) take about four and a half hours, with two or three services a day; the Alvia route runs via Cáceres. From Seville, the Media Distancia takes around three and a half hours. The station is a kilometre north of the old town, a 15-minute walk.
Long-distance buses (Avanza, Alsa) run from Madrid, Seville, Lisbon, and Badajoz, often with more frequent and faster services than the train. The nearest airport with regular flights is Badajoz (BJZ), 65 km west, with a handful of domestic routes; for most travellers the practical entry points are Madrid or Lisbon, with a connection by rail or road.