Ostrava (Polish Ostrawa, German Ostrau) is a statutory, regional and university city in the northeast of the Czech Republic in the Moravian-Silesian Region, near the border with Poland. It is located at the confluence of the rivers Odra, Opava, Ostravice and Lučina. Ostrava is the third largest city in the Czech Republic, the second largest city in Moravia and the largest city in Bohemian Silesia in terms of population and area (it lies on the border of these two historical countries). Approximately 288,000 people live here, but almost 1 million people already live in the entire Ostrava agglomeration, which is the second largest agglomeration in the Czech Republic after Prague. Together with the Polish Katowice, it forms the Silesian metropolitan area with 5.3 million inhabitants.

Ostrava grew up as an industrial center of the coal basin. For its mining and metallurgical industry in the past called the "steel heart of the republic", it underwent significant changes after 1989. As a result of industrial restructuring, mining activity was curtailed and the last coal was mined in 1994. The mining area is witnessed by the Lower Vítkovice area. a former industrial complex with a unique set of industrial architecture aspiring to be inscribed on the UNESCO World Heritage List. There are many theaters, galleries and cultural houses in Ostrava. The most famous cultural events organized in the city include the Colors of Ostrava and Beats for Love music festivals, the Janáček's May and St. Wenceslas Music Festival, the Shakespeare Festival. The Zlatá tretra athletics race is also held every year. Higher education in Ostrava is represented by the University of Mining - Technical University of Ostrava and the more generally focused University of Ostrava.

For 2014, Ostrava was a European city of sports. In 2004 and 2015, together with Prague, it organized the IIHF Ice Hockey World Championship. At the beginning of 2017, the European Figure Skating Championships took place in Ostrava, and in September 2018, the IIAF Continental Cup took place at the Municipal Stadium. At the turn of 2019 and 2020, Ostrava, together with Třinec, hosted the Junior World Hockey Championship.