From time to time construction in downtown San Pedro will turn up burials and other cultural remains of what was once an important Maya community. Ambergris Caye figured prominently in the Maya trade system, serving as a way-station and transshipment point on the far-flung canoe trade connecting the Maya and non-Maya worlds. Large ocean-going dugouts (the Maya never invented the sail) transported salt, pottery, dried fish, seashells and probably textiles from the coastal zones of northern Yucatan to Ambergris Caye. Here it is believed the materials were off-loaded and transferred to the smaller canoes that were capable of negotiating the shallow, narrow inland rivers and streams leading into the highlands. Returning canoes would bring jade, obsidian, basalt (for manos and metates), furs, feathers and a variety of forest products that would ultimately arrive on Ambergris Caye for further transport to the coastal zones.
While the archeology of Ambergris Caye is still poorly known, it is clear that the trade system was in place well before the Christian Era. Initially, the trade was focused on an exchange of exotic goods between members of the elite ruling class as a way of reinforcing their elevated status. Gradually, the exchange of commodities, those items or materials of more practical value, became increasingly important, particularly after the rapid decline of the Maya theocratic state after about 800 A.D. With the abandonment of the great inland cities and ceremonial centers, the road system formerly connecting the population centers also deteriorated, rendering the overland trade routes relatively unimportant. It was at this point that the Putuun Maya from the west coast of the Yucatan, who had long been engaged in ocean-going canoe trade around the Yucatan and Gulf Coast, saw a window of opportunity and expanded their influence by incorporating the entire coast of the western Caribbean into their trade routes. Sites from this period on Ambergris Caye show an increase in the materials from Mexico and Guatemala.
It is not generally known that the Maya constructed the cross-island canal that constitutes the international boundary between Mexico and Belize. There is very convincing evidence that Bacalar Chico was dug to facilitate the passage of trade vessels from the windward side of the island to the Bay .of Chetumal sometime around 600 A.D. This canal cuts about sixty miles off the trip from Yucatan to the rivers emptying into Chetumal Bay which connected the highlands with the sea. The oldest map of the area that clearly shows the canal is dated 1726, long before the first serious attempt. at settlement. Possibly the oldest historic reference to Ambergris Caye comes from a sixteenth century letter recently discovered in the Spanish archives. The letter is a quasi-legal petition for a land grant from the governor of Jamaica by a Spanish sea captain who had spent two year locating fresh water and salt sources in what he describes as the Chetumal area. While the island is not mentioned by name, scholars who have mined the document have concluded that the captain was referring to Ambergris Caye. Sometime around 1300 or 1400 A.D., most of Ambergris Caye seems to have been abandoned. There is a strong possibility that a couple of sites may have been occupied up until the Spanish arrival in the sixteenth century, but the glory days of the Maya trade system was a thing of the past.