Quite a special place. At Tulamben Bay there is a shipwreck from the World War II at only 3 meters deep! This means you can see the wreck without having to use diving equipment. The wreck is currenly providing shelter to a wide range of tropical fish.
Rafting on the Ayung River, straight through the jungle of Ubud. Expect rapids of class 2 or 3 (depending on the season). Enough for a nice adrenaline boost, but under professional guidance perfectly safe.