Wat Si Chum

The draw here is Phra Achana, a seated Buddha nearly 15 meters tall, wedged into a square mondop with walls close enough that the figure feels bigger than it already is. There's no roof, so the sky does the lighting. You get your first look through a tall slit in the stone facade, which is the whole point of the design, and it works. Come at 07:30 when the gates open and the light is soft and you'll have it more or less to yourself.

Inside the hollow walls there's a staircase lined with engraved slate slabs showing scenes from the Jataka tales, the Buddha's past lives. Access isn't always granted, so don't build your day around it. The exterior and that narrow view are what people remember anyway. The grounds are open and uncluttered, typical of this part of the Sukhothai Historical Park, so it's an easy stop to fold in with the other ruins by bicycle rather than a destination on its own.