Ko Samui often called just Samui is an island in the Gulf of Thailand, some 700km south of Bangkok and about 80km from the eastern coastline of southern Thailand.
Ko Samui is all in all a fairly big place. The most popular and commercialised beaches are Chaweng and Lamai, while the northern beaches and their adjacent villages of Mae Nam, Bophut, Bang Ruk (Big Buddha) and Choeng Mon are more peaceful choices, and the west coast beaches are still (comparatively) quiet.
Clockwise from Nathon on the west coast, the main beaches are:
Nathon - Samui's port and administrative center, but with little to attract the tourist
Mae Nam - a quiet and beautiful beach on the northern coast
Bophut - known for its Fisherman's Village, laid-back but growing fast
Bang Ruk - at the northeastern tip, home of the Big Buddha
Choeng Mon - quiet North shore beach
Chaweng - the largest and most-developed beach, with a curious mix of luxury hotels and backpacker guesthouses and a hopping nightlife
Lamai - Samui's "second" beach south of Chaweng, more backpackery than Chaweng
South Coast - the small beaches of Ban Hua Thanon, Na Khai, Laem Set, Bang Kao and Thong Krut
If you are looking for a place to stay then you better check out HotelsCombined.com – this website compares all major travel sites and lets you know who has the best deals. To see their list of hotels in Koh Samui go to this page. Another way to get some good rates is to just turn up at the hotel of your choice and ask for the best rates, or simply call the hotel directly.
Samui is an island in the Gulf of Thailand, some 700km south of Bangkok and about 80km from the eastern coastline of southern Thailand. 
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