Wat Mahathat in Sukhothai is a historical temple located within Sukhothai historical park. Sukhothai is about 5 hours’ drive from Bangkok with the distance of about 450 km. I really do not recommend visiting Sukhothai on a day trip from Bangkok because it would be best to take time to go around Sukhothai.
Despite having been damaged in fire long time ago, the Buddha images are still magnificent. Our group went there and sat to chant as well as meditated for a short while under the shady trees.
About Wat Mahathat as per the notice temple:
Situated in the heart of the city is the most important empire as the principle temple of Sukhothai. This significant temple comprises of the main chedi (stupa), assembly halls (vihara), mandapa, an ordination hall (Ubosatha) and 200 subordinate chedis.
The main chedi has the graceful shape of a lotus bud, which characterizes the art of Sukhothai. Surrounded by 8 chedis, the four at the corner belong to Hariphunchai, Lanna style and the four in between have Prang-shaped chedis, which were influenced by the Khmer art.
The base of the main chedi is decorated with relief-stucco of 168 Buddhist disciples walking with their hands clasped together in salutation. At both sides of the main chedi is situated with two standing Buddha images called Attharot, 12 meters in height.
There is a huge bronze Buddha image or golden Buddha image in stip inscription No. 1 enshrine in the royal vihara in front of the main chedi. This image was removed to Suthat temple in Bangkok by King Rama I and it was later named Phra i Sakkayanmuni.
Note: There is another famous ancient temple also known as Wat Mahathat located in Ayutthaya where the iconic Buddha head statue is located. Both are different temples located at totally different provinces.
I have personally been to Sukhothai historical park- once via car (a friend drove us) and the second time via chartered van from Bangkok. It is worth to take at least 2 days to stay overnight in Sukhothai to explore the place. Compared to Ayutthaya, Sukhothai tend to have less visitors, probably because it is much further from Bangkok. I appreciate the peace and quiet that I can find in Sukhothai.
When visiting the ancient temples of Sukhothai, especially Wat Mahathat, I am often reminded of similar ancient temples in Anuradhapura in Sri Lanka.