MADRID -- Two military planes laden with 17 tons of silver and gold coins scooped up from a Spanish warship that sank during a 1804 gunbattle are back in Spain, ending a 200-year odyssey that took the treasure from an ocean floor to Florida courtrooms.

The planes landed Saturday with the 594,000 coins and other artifacts retrieved after a five-year legal wrangle with the Florida-based salvage company Odyssey Marine Exploration, which had taken the haul to the U.S. in May 2007.

The deep-sea explorers found the treasure in a shipwreck, believed to be Nuestra Senora de las Mercedes, off Portugal's Atlantic coast. British warships had sunk it as it approached Spain from South America.

The coins are estimated at up to $500 million, making the haul one of the richest ever.