Mexico City is the capital city of Mexico, and the largest city in North America. The city is officially divided into 16 delegaciones which are in turn subdivided into colonias, of which there are around 250; however, it is better to think of the city in terms of districts to facilitate the visitor getting around.
Polanco refers to an area of Mexico City north of Chapultepec Park. This district is delimited by Paseo de la Reforma to the south, Boulevard Manuel Avila Camacho to the west, Avenida Ejercito Nacional to the north and Avenida Mariano Escobedo to the east.
Tlalpan and Pedregal is a district of Mexico City. Tlalpan comprises several small towns south of Mexico City, including Tlalpan itself, Chicalcoyotl, San Pedro Martir, San Andres Totoltepec, Xicalco and San Miguel Ajusco.