Phitsanulok is an important, historic city in lower northern Thailand and is the capital of Phitsanulok Province, which stretches all the way to the Laotian border. Phitsanulok is one of the oldest cities in Thailand, founded over 600 years ago. It is probably best known as the birthplace of King Naresuan, who freed the country from Burmese domination in the late 16th century, and that of his brother and successor King Ekathosarot (Sanphet III). As the crossroad between the northern and central regions of the country, it has long been important both for political and strategic reasons, and was fought over many times in centuries past. Phitsanulok was the capital of Thailand for 25 years during the reign of King Boromma Trailokanat of Ayutthaya. On the banks of the Nan River, the city was originally a small Khmer outpost known as Song Kwae, before the Khwae Noi River changed its course in the 11th century CE. Phitsanulok was also a provincial center of the Angkorian Empire during the Angkorian period. Phitsanulok is home to Naresuan University and Pibulsongkram Rajabhat University, as well as to a major Royal Thai Army base.