By Car -- To reach Puerto Barrios by car, take the Carretera al Atlántico (CA-9) out of Guatemala City. Puerto Barrios is the end of the line some 295km (183 miles) to the northeast.
By Bus -- Litegua (tel. 502/7948-1002 in Puerto Barrios, 2220-8840 in Guatemala City; www.litegua.com) has direct daily service between Guatemala City and Puerto Barrios. The Litegua terminal in Guatemala City is at 6a Calle and 9a Avenida, Zona 1. The first bus leaves for Puerto Barrios at 4:30am, and they run at least every hour, often on the hour and half-hour, until 6pm. Return buses have a similar frequency, but between the hours of 1am and 4pm. The bus station in Puerto Barrios is at the corner of 6a Avenida and 9a Calle. The trip takes about 5 hours each way. Fares are between Q60 and Q120 ($8-$16/£4-£8) one-way. Splurge for one of the "executive" or "deluxe" buses, which are more modern, comfortable, and faster.
By Boat -- Scheduled boats run from Puerto Barrios to Livingston at 10am and 5pm. The 90-minute trips costs Q15 ($2/£1). Faster boats leave throughout the day, roughly every 2 hours or, when demand is high, as they fill to capacity, and charge Q30 ($4/£2). These make the run in just 30 minutes -- well worth the extra $2 -- and run roughly between 6:30am and 4pm.
Transportes El Chato (tel. 502/7948-5525) runs a daily boat to Punta Gorda, Belize, at 10am. The return boat leaves Punta Gorda at 2pm. The one-way ride takes around 1 hour and costs Q150 ($20/£10). Before heading to Punta Gorda, you must have your passport stamped at the Immigration Office, 9a Calle and 2a Avenida (tel. 502/7948-0327), which is located just 1 block from the dock.
Boats to and from Livingston, as well as to Punta Gorda, Belize, use the municipal dock at the end of 12a Calle.
Taxis are plentiful in Puerto Barrios, and cabs are always waiting to meet incoming boats from Livingston and Punta Gorda, as well as all incoming buses. Given the seediness and relative insecurity of the city, I'd recommend taking a taxi most places. If none are readily available, have your hotel call you one, or try Taxis Unidos (tel. 502/7948-0864) or Taxis Izabal (tel. 502/7948-0594).
While Puerto Barrios remains a busy port, much of the commercial traffic was shifted just down the bay to Santo Tomás de Castillo after a 1976 earthquake damaged many of the port facilities. Several banks, shops, and services are located in the compact downtown area. In the case of a medical emergency, contact the local hospital (tel. 502/7948-3073).