The temple stands near Bangkok city hall, just on the opposite side of the road and The Giant swing between them. You can start from The Democracy Monument and keep walking about 100 meters to the temple. It is located south of the Democracy Monument.
The Brief History of Suthat Thewararam Temple in Bangkok Thailand
King Rama I founded the temple at the central area of the city at that time, and built the sizable wiharn as the Wiharn of Wat Phanan Choeng in Ayutthaya. Then the Sukhothai style bronze Buddha image, brought from Wat Mahathat in Sukhothai, and was installed inside the Wiharn. The image was called Phra Toh or Phara Yai means big Buddha image. The Wiharn (main hall) was completed in the reign of king Rama III. Then the Ubosot (ordination hall) was built along with the principal Buddha image. The temple was then named Wat Suthat Thewararam. Later, king Rama IV named the principal image inside the Wiharn Phra Phuttha Srisakkayamuni and the principal image inside the Ubosot Phra Phuttha Trilokachet.