Quintana Roo, officially Free and Sovereign State of Quintana Roo, is one of the 31 states which, with the Federal District, comprise the 32 Federal Entities of Mexico. It is divided in 10 municipalities and its capital city is Chetumal.
It is located in Southeastern Mexico, on the eastern part of the Yucatán Peninsula. It is bordered by the states of Yucatán to the northwest and Campeche to the west. To the north and east, Quintana Roo borders the Caribbean Sea and to the south, Belize. It also claims territory which gives it a small border with Guatemala in the southwest of the state, although this disputed area is also claimed by Campeche.
Quintana Roo is home of the city of Cancún, the islands of Cozumel and Isla Mujeres, the towns of Bacalar, Playa del Carmen and Akumal, as well as the ancient Maya ruins of Chacchoben, Cobá, Kohunlich, Muyil, Tulum, Xel-Há, and Xcaret. The Sian Ka'an Biosphere Reserve is also in the state.
The state officially covers an area of , but since 1997 there is a boundary dispute with the states of Yucatán and Campeche over an area of approximately .
The statewide population is expanding at a rapid rate due to the construction of hotels and the demand for workers. Many immigrants come from Yucatán, Campeche, Tabasco, and Veracruz. The state is frequently hit by severe hurricanes due to its exposed location, the most recent and severe being Hurricane Dean in 2007, making landfall with sustained winds of 280 km/h (175 mph), with gusts up to 320 km/h (200 mph).
On February 1, 2015, Quintana Roo officially adopted a new time zone, Southeast, which corresponds to Eastern Standard Time (EST).
The area that makes up modern Quintana Roo was long part of Yucatán, sharing its history. With the Caste War of Yucatán starting in the 1840s, all non-natives were driven from the region and the independent Maya nation of Chan Santa Cruz was centered on what is now the town of Felipe Carrillo Puerto.
Quintana Roo was made a territory of Mexico by decree of President Porfirio Díaz on November 24, 1902. It was named after an early patriot of the Mexican Republic, Andrés Quintana Roo. The Mexican army succeeded in defeating most of the Maya population of the region during the 1910s, and in 1915 the area was again declared to be legally part of the state of Yucatán.
Quintana Roo was granted statehood within the United Mexican States on October 8, 1974. It is the Mexican Republic's youngest state.