In short
Koh Chang — Elephant Island — is eighty per cent covered in protected primary forest, with peaks at seven hundred metres and waterfalls inland.
It lies near the Cambodian border, in the east of the gulf, far from the southern islands. That long spared it the crowds of Samui or Phuket.
What it really costs
The island is cheaper than the big southern islands for equivalent comfort. The west coast holds the accommodation, from dorms to resorts.
The national park covering the interior has its own entry fee, collected at the waterfall access points. It comes on top of transport.
What nobody tells you
The road around the island is very steep in places, with abrupt descents. It is one of the spots in Thailand where scooter accidents are most frequent.
Many businesses close from May to October, in the rainy season, and the island runs at half speed.
The waterfalls are seasonal: dry by the end of the dry season, they are only worth the detour after the rains.