Pärnu is the fourth-largest city in Estonia and third in terms of the ethnic Estonian population. Situated in southwest Estonia, Pärnu is located 128 kilometres (80 mi) south of the Estonian capital, Tallinn, and 176 kilometres (109 mi) west of Estonia's second-largest city, Tartu. The city sits off the coast of Pärnu Bay, an inlet of the Gulf of Riga, which is a part of the Baltic Sea. In the city, the Pärnu River drains into the Gulf of Riga.

Estonia, officially the Republic of Estonia, is a country by the Baltic Sea in Northern Europe. It is bordered to the north by the Gulf of Finland across from Finland, to the west by the sea across from Sweden, to the south by Latvia, and to the east by Lake Peipus and Russia. The territory of Estonia consists of the mainland, the larger islands of Saaremaa and Hiiumaa, and over 2,300 other islands and islets on the eastern coast of the Baltic Sea, covering a total area of 45,335 square kilometres (17,504 sq mi). Tallinn, the capital city, and Tartu are the two largest urban areas of the country. The Estonian language is the indigenous and official language of Estonia, and it is the first language of the majority of the country's population of 1.4 million.