Bora Bora lies 150 miles northwest of Tahiti in the Society Islands. The main island, home to 4,225 inhabitants, is in the center of a multicolored lagoon, surrounded by offshore "motu" islets inside a protective coral necklace. Its lagoon is world-famous for its beauty. A partially paved road circles the island, passing colorful villages, archeological sites, and old Army bunkers and cannons left over from WWII, when 5,000 American GIs made a "friendly invasion."