Rayong province
Rayong province is located to the southeast of Chonburi and west of Chanthaburi. It is best known for popular Ko Samet and, among English teachers, a TEFL teaching centre. While many beaches line Rayong province's coastline, these are little visited by foreign travellers and backpackers, who tend to head straight offshore from the fishing port of Ban Phe to Ko Samet.
The same-named provincial capital is a bleak, charmless spot and the nearby power stations do seem to add a little something to the air -- very few travellers opt to stay in Rayong town.
By far the most popular destination in Rayong province is pretty Ko Samet. Ostensibly a national park, as with many if not most of Thailand's national parks home to beachfront land, encroachers have well and truly had their way here; that the National Parks Authority continues to charge an entrance fee is pretty ridiculous. Despite being over-developed, Ko Samet is certainly not under-appreciated, drawing a steady weekend crowd of escapees from Bangkok, though mid-week it can be quite sleepy. Over holidays, the island is often packed.
Further east from Ko Samet lies the pretty Ko Mun Nork -- a private island with a single resort sitting on the best part of it. Popular for weddings, private raves and romantic getaways, Ko Mun Nork isn't the cheapest spot around, but if you're after a splurge, it may be worth checking out.
Nature lovers may be interested in the Khao Chamao - Khao Wong national park, but it is better visited from adjacent Chanthaburi province.
