This site was added to the UNESCO World Heritage Tentative List on September 23, 2002 in the Cultural category.

[4] The fort is under the administrative care of the Guatemalan Institute of Tourism (INGUAT – Instituto Guatemalteco de Turismo).

[5] The river water around the fort has been found to be heavily contaminated with coliform bacteria resulting from local pollution.

[8] San Felipe had continuous occupation from the Mesoamerican Middle Preclassic period (c.1000–400 BC) and was still inhabited when the Spanish first arrived in the region in the mid 16th century.

[2] San Antonio was the main port for receiving Spanish shipping carrying goods for the Captaincy General of Guatemala and was responsible for supplying and garrisoning the fort.

The latter post was in name only, since the towns were soon abandoned due to constant slave raids by the Mosquito Zambo that left the Motagua delta and shores of Lake Izabal largely deserted, with those inhabitants that did not flee being sold into slavery in the British colony of Jamaica.

[5] The fort consists of a semicircular bastion enclosed behind two converging outer walls, each terminating in a roughly square tower.