Bentota is located on the southern coast of Sri Lanka, close to the popular tourist city Galle. This is an ideal location for a family vacation, where plenty of water sports can be enjoyed as well. You have jet skiing, banana boat riding, knee boarding, and whatnot in Bentota itself while venturing a few km away from it will bring you to ideal locations for surfing. You will find plenty of restaurants, a number of B&Bs, and many a beach hotel. Sri Lanka prides itself on its sun, sand, and the sea – Bentota being an ideal candidate to prove this point in the luxury of star class hotels.
The problem with the area being a major tourist destination is that it is often crowded. You are unlikely to have the beach to yourself under any circumstance. Even if you are to visit during the offseason, at least a few dozen visitors will be in the sea, along with you.