Down at the south end of the lake, Phra Mahathat Kaen Nakhon, the gorgeous nine-storey stupa at the heart of this important temple, makes this Khon Kaen's one must-see attraction. It features enlightening modern murals depicting Isan culture and Khon Kaen's history; various historical displays, including a collection of rare Buddha images on the 4th floor; and a 9th-floor observation deck. The monks open the door to the upper floors when they are ready, which is roughly 7.30am to 5pm.