Kesklinn is one of the 8 administrative districts of Tallinn, the capital of Estonia. It is situated on the Tallinn Bay and bordered to the northwest by the district of Põhja-Tallinn, to the west by Kristiine, to the southwest by Nõmme, to the east by Lasnamäe and Pirita, and to the south by Rae Parish, beyond Lake Ülemiste. The island of Aegna, located in the Tallinn Bay, also falls within this administrative district. Kesklinn has an area of 30.6 km2 (11.8 sq mi) and a population of 57,731 ; population density is 1,886.6/km2 (4,886/sq mi).

Tallinn is the capital and most populous city of Estonia. Situated on a bay in north Estonia, on the shore of the Gulf of Finland of the Baltic Sea, Tallinn has a population of about 461,000 and administratively lies in the Harju maakond (county). Tallinn is the main governmental, financial, industrial, and cultural centre of Estonia. It is located 187 km (116 mi) northwest of the country's second largest city, Tartu; however, only 80 km (50 mi) south of Helsinki, Finland, also 320 km (200 mi) west of Saint Petersburg, Russia, 300 km (190 mi) north of Riga, Latvia, and 380 km (240 mi) east of Stockholm, Sweden. From the 13th century until the first half of the 20th century, Tallinn was known in most of the world by variants of its other historical name Reval.