Koh Tan and Koh Mad Sum have a history rooted in local fishing traditions. Koh Tan, once a quiet fishing island, gained attention for its natural beauty, especially its coral reefs and crystal-clear waters, which have made it a top spot for snorkeling and diving. Over the years, tourism has grown, though the island still retains its peaceful, undeveloped charm. Koh Mad Sum, being even smaller, was primarily used by fishermen as a base, and its shallow waters and untouched landscapes attract those seeking a quiet retreat. Both islands are now part of sustainable tourism efforts to preserve their natural environments while offering visitors a serene escape from the more touristy areas of Koh Samui.