Not far from Wat Mahathat is the Ramkamhaeng National Museum. (No photos allowed, unfortunately.) It is relatively small, but worthwhile with helpful explanatory text in both Thai and English. Unsurprisingly, the bulk of the collection consists of Buddhas, made of wood, stone, terracotta, bronze, gold, etc., from the Sukhothai period as well as others.
The museum also has some other interesting items including pottery, statutes of Hindu deities, ceramics, weapons, examples of temple ornamentation (e.g., carved dragons), etc. One of the most popular displays includes a set of donut shaped stones euphemistically labeled "slabs covering a lavatory." Ancient toilet seats!
♥ Visit Tagulandang Island ♥