There are litreally hundreds of ship wrecks scattered across the gulf of thailand from huge tankers, to ancient pottery wrecks plus many undiscovered WWII Japanese and Allied vessels. M.V. Evolution regularly goes in search of new wrecks, here are a few of the wrecks we know about...
HTMS Chonburi, Pak 1 (The once Vertical Wreck), Concrete wreck, Cargo Ship...

HTMS Chonburi

Depth: 45 m

Distance from Koh Chang: 3 Hours

Ship length: 70m

Width: 10m

A wreck of approx 70meters size marked by 2 large red buoys and is situated approx 200meters from the shore on the South Westerly corner of Koh Chang.
The warship(s), Sinking quite close to shore having been 'beached' in relatively shallow water in an area of sometimes strong currents and often poor 'muddy water' visibility, this large wreck must be dived at the right time to be seen at all. The ideal time is when a 'neaps' slack tide occurs around mid-day, during a prolonged period of calm flat seas. If dived at this time, visibility of 5-10m may be expected. If randomly dived during a tidal run in average weather, you might not see the wreck till you hit it (visibility of 30cm to 2m is not fun!)