Archaeological excavations at Brickell Point in 1998, uncovered a circle of postholes and cut basins into the limestone bedrock measuring 11.2 meters in diameter. Within the floor of the feature were the skeleton of a shark, the cranium of a of a bottlenosed dolphin, and the shell of a sea turtle – all aligned in an east – west axis. Artifacts included numerous non-local materials such as basaltic celts from the Appalachian Mountains, copper from the Mid-West, galena, and other exotic artifacts.

Since that discovery twelve other circles have been uncovered at the mouth of the Maimi River. Radiocarbon dates of AD 200-700 indicate that this complex was a major town and trade center 1500 years before the creation of the City of Miami. The evidence of thousands of postholes indicates likely elevated structures paralleling the river. Other postholes may have been supports for extensive fishing nets stretched for mending and to dry. These remains are associated with the Tequesta who, like the Calusa, were a stratified society that did not practice agriculture, and like the people of the Northwest, created a complex society based on maritime resources. The results of excavations at the mouth of the Miami River from 1980 to present provide a view of a previously little known site complex that is the southernmost prehistoric trade center in the United States.