Head south on Petchakasem Road and look for the signs.
It's about nine kilometres from Cha-am, on the left. It's a complex of golden teak houses on stilts with louvered windows and a maze of walkways connecting them. The airy rooms were designed to beat the heat in the days before air-con, and the raised walkways enabled the royals and their guests to get around without getting their tootsies wet during flash floods.
It's well-maintained and the architectural design somehow evokes both the austerity of a life devoted to contemplating the Buddha and a summer of fun on the beach. Several rooms feature exhibits depicting how the inhabitants and their servants lived. There isn't a lot of English language information, so if you want to know what you are looking at, you'll have to hire an English-speaking guide.
The Travelfish newsletter is sent out every Monday and is jammed full of free advice for travel in Southeast Asia. You can see past issues here.