Old Bagan is an ancient city in Myanmar that has tons of religious buildings
The ancient city of Bagan was once the capital of the Bagan Kingdom, which thrived between the 9th to the 13th century. During its heyday, a startling number of religious buildings were constructed, including some of the best examples of Burmese-style temples.
The city lost much of its population in the late 1200s after the Mongols invaded the empire. The site is vast and slightly hard to access, so hot air balloon tours are probably the best way to experience its sights.