Pre-Columbian rafts voyaged as far as Mexico and introduced metallurgy to the civilizations of that country. Some scholars and adventurers of the 20th and 21st century have asserted that the rafts and their crews journeyed thousands of miles across the Pacific to Polynesia, most notably Thor Heyerdahl who reached Polynesia on the Kon-Tiki raft. Several other people and groups have also built rafts based on prehistoric models and undertaken trans-Pacific voyages. Balsa is the Spanish word for raft. The use of rafts for commerce on the coasts of Peru and Ecuador, from northern Chile to southern Colombia, continued until the late 19th
Tangaroa Expedition solar panels, portable computers, and desalination equipment. The crew posted to their website. Tangaroa's six-man crew was led by Norwegian Torgeir Higraff and included Olav Heyerdahl, grandson of Thor Heyerdahl, Bjarne Krekvik (captain), Øyvin Lauten (executive officer), Swedish Anders Berg (photographer) and Peruvian Roberto Sala. Tangaroa was launched on the same day that Kon-Tiki had been—April 28—and it reached its destination on July 7, which was 30 days faster than Heyerdahl's Kon-Tiki which had taken 101 days for the voyage. Tangaroa's speed was credited to the proper use of the quara centerboards in navigation. Heyerdahl had not known how to