Gatchina is a town and the administrative center of Gatchinsky District in Leningrad Oblast, Russia. It lies 45 kilometers (28 mi) south-south-west of St. Petersburg, along the E95 highway which links Saint Petersburg and Pskov. Population: 92,937 (2010 Russian census); 88,420 (2002 Census); 79,714 (1989 Soviet census).

Gatchinsky District is an administrative and municipal district (raion), one of the seventeen in Leningrad Oblast, Russia. It is located in the southwestern central part of the oblast and borders with Krasnoselsky, Moskovsky, and Pushkinsky Districts of the federal city of St. Petersburg in the north, Tosnensky District in the east, Luzhsky District in the south, Volosovsky District in the west, and with Lomonosovsky District in the northwest. The area of the district is 2,868.7 square kilometers (1,107.6 sq mi). Its administrative center is the town of Gatchina. Population : 140,210 (2010 Russian census); 132,010 ; 138,022 (1989 Soviet census).