Buddhism reached Sukhothai through monks and traders from Sri Lanka, a large island country southeast of India. The kings supported Buddhism and built many temples (wat).
At the UNESCO Sukhothai Historical Park, you can still see:
Wat Mahathat, the main temple, once used for important ceremonies
Large Buddha statues, often seated or walking, showing calm and peace
Stupas (round or bell-shaped structures) used to hold sacred objects
These buildings show how important Buddhism was to daily life and government.