At the entrance to the river there is a small Spanish colonial fort, the Castillo de San Felipe de Lara, built to stop pirates entering the lake from the Caribbean when this part of Central America was an important shipping staging point.

On one side of the bridge is the town of Fronteras, commonly referred to by the name Río Dulce, the local center of commerce for the area.

The park covers an area of 130 square kilometres (50 sq mi)[1] along the banks of the Dulce river and the El Golfete.

They reached some locations using the railroad service in Guatemala, which was controlled by the American International Railways of Central America (IRCA), owned by the United Fruit Company[2]— and had major stations at Puerto San José, Guatemala City and Puerto Barrios.

[3] The railroad company offered tours to visit the UFCO banana plantations in Izabal and the Maya city of Quiriguá —which at the time was placed within UFCO property— and offered their visitors the option to comfortably sail Río Dulce and Lake Izabal to Livingston in one of their steam boats.