A detailed analysis of historical records was used to create an accurate replica of a pre-Columbian, Northwestern South American sailing raft. La Mantena-Huancavilca was built in Ecuador and voyaged for several weeks off Ecuador and Colombia. The raft, controlled by native methods including mobile lee boards and two lateen sails, was found to have excellent sailing characteristics, being able to carry out all basic maritime maneuvers including sailing very close to the wind. Although the vessel was lost to the shipworm, Teredo navilis, the project generated much data on the options and constraints that would have conditioned the behavior of pre-Columbian mariners on this coast.