Soon after Christopher Columbus discovered the new world, Spain began to send fleets of ships to the new world to pick up and bring back amazing amounts of treasure. In 1515, a port called San Cristóbal de la Habana was founded by the Spanish conquistador Diego Velázquez de Cuéllar, possibly near the present town of Batabanó on the south coast of the island where Spain could repair their ships and fortify their provisions for their non-stop trip back to Seville, Spain. Columbus had established trade routes which included sailing north with the Gulf Stream up the east coast of Florida. Earlier treasure ships carried riches from the Incas, the Mayans, and the Aztecs, while later ships carried mined treasure. The ships in these fleets averaged in size from 100 tons for a small ship, to 800 tons for a large ship. With no way to forecast the weather, hundreds of ships were caught in storms, and in some cases, entire fleets would sink.