The best way to get to Fronteras (the main crossroads at Rio Dulce) is by Pullman bus. There are several companies that run the highway from Guatemala City to Fronteras. Litegua runs the fastest buses, while Linea Dorada has 'first-class' buses with air-conditioning and snack service. The trip takes 5-6 hours.
Shuttles also run from Antigua a few times a week. Check the schedule on our Antigua section.
Getting Around
The primary mode of transportation once you arrive in Rio Dulce is by lancha, a speedboat taxi service that runs up and down the shores of the river throughout the day. They can easily be arranged through your accomodations.