Sweet little Ko Mak (เกาะหมาก) measures just 16 sq km and doesn’t have any speeding traffic, wall-to-wall development, noisy beer bars or crowded beaches. Its palm-fringed bays are bathed by gently lapping water and there's a relaxed vibe. The island's history dates back to ownership by just one family, and there's a largely local movement that tries to keep the impact of tourism sustainable. The interior is a utilitarian but peaceful landscape of coconut and rubber plantations.
Although small, Ko Mak has a decent restaurant and bar scene back from Ao Khao, a couple of dive outfits and boat trips out to nearby islands, so there's a bit to do in between hanging out on the beach.
Visiting the island is easier in high season (December to March); during low season (May to September) many boats stop running.