Wat Phra Kaew itself, generally known to the Thais as Wat Phra Si Rattana Satsadaram, is perhaps the main attraction. This is Thailand's most important and sacred temple, so you're expected to act with due respect inside it. It houses the tiny (between 60 and 75 cm) Emerald Buddha, which is located high above the heads of the worshippers and tourists. Not much is known for certain about the statue, except that it isn't actually made of emerald but rather of green jade or jasper. Getting a good look at it is difficult as photography is forbidden inside the temple, and it's perched so high up inside it's glass box that it's difficult to really see.