The part of today's downtown Port of Spain closest to the sea was once an area of tidal mudflats covered by mangroves. The first Spanish buildings here, in the 16th and 17th centuries, were open mud-plastered ajoupas, interspersed between large silk cotton trees and other trees. The fort was a mud-walled enclosure with a shack inside, a flagpole, two or three cannon, and few Spanish soldiers. This was captured during Walter Raleigh's expedition in April 1595. The Caribs were transient, travelling to the mainland (now Venezuela) and up the Orinoco River. The French naval commander Comte D'Estrées visited in 1680, and reported that there was no Port of Spain. But in 1690, Spanish governor Don Sebastien de Roteta reported in writing to the King of Spain: