Buddhist temple-city on the Irrawaddy in Myanmar — 3,500 surviving temples and pagodas from 11th-13th centuries. Inscribed 2019.
From Wikipedia
Bagan is an ancient city and a UNESCO World Heritage Site in the Mandalay Region of Myanmar. From the 9th to 13th centuries, the city was the capital of the Pagan Kingdom, the first kingdom that unified the regions that would later constitute Myanmar. During the kingdom's height between the 11th and 13th centuries, more than 10,000 Buddhist temples, pagodas and monasteries were constructed in the Bagan plains alone, of which the remains of over 2,200 temples and pagodas survive.