The first town emerged on the left bank of the Pärnu River no later than in 1251 when Hendrik (Henricus), the bishop of Ösel-Wiek, ordered for a dome church and a town around it to be built at the site of modern day Old-Pärnu. The town was destroyed already in 1263 when Treniota, the Prince of Samogitia, and his troops burnt down the church as well as the town. It is likely that a town was also emerging on the right bank of the Pärnu River because a commandery was appointed in New-Pärnu merely two years later, and there was probably also an active Town Council.
Medieval New-Pärnu was one of the biggest towns in Old Livonia according to its area (62,000 m2) and population, falling behind only Riga, Tartu and Tallinn. Hypothetically, New-Pärnu may have been home to around 1,100 people during the 16th century, 600 of which lived inside the town walls. The economy of the town was largely based on the activities of Hanseatic merchants and artisans. Dwellings were initially mostly made of wood, however, stone houses had already become dominant by the beginning of the 16th century. In addition to dwellings, there were also taverns, stone granaries with cellars, stables, garden plots and artisans’ shops. At least 25 artisan trades existed in the town at the start of the 16th century.
The birth of the resort was complicated. The idea emerged at the beginning of the 19th century. In 1838, at a time of economic instability, the number of visitors was modest. During the peak season around 150 summer visitors at most, stayed in Pärnu. However, in 1889 Pärnu saw a revival of the idea of the Resort . The growth of the resort became a key aspect, which shaped the development and the image of the town for the years to come.
In the 21st century, thanks to the vision of the Municipality of Pärnu, pursuing sustainable development of the resort, Pärnu has entered the world destinations map as a top-ranking resort by the Baltic Sea.