Děčín is a city in the Ústí nad Labem Region of the Czech Republic. It has about 47,000 inhabitants. It is the 7th largest municipality in the count…Děčín is a city in the Ústí nad Labem Region of the Czech Republic. It has about 47,000 inhabitants. It is the 7th largest municipality in the country by area. Děčín is an important traffic junction. The name is derived from the personal Slavic name Děk.