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.

These include the parliament building (Toompea Castle), City Government, The Estonian National Opera, Estonian and Russian drama theatres, The National Library, Kadrioru and Kalevi stadiums and a considerable number of museums, theatres and government agencies.

One of the economy's key drivers is tourism from Helsinki, Finland, which is connected to Tallinn by rapid ferry traffic.

Kesklinn has 21 subdistricts (Estonian: asum): Aegna, Juhkentali, Kadriorg, Kassisaba, Keldrimäe, Kitseküla, Kompassi, Luite, Maakri, Mõigu, Raua, Sadama, Sibulaküla, Südalinn, Tatari, Tõnismäe, Torupilli, Ülemistejärve, Uus Maailm, Vanalinn and Veerenni.