an arrondissement of the department of the Upper Rhine in France, extending over 341 square miles, and comprehending nine cantons and 191 communes, with 90,769 inhabitants. The chief place is the city of the same name, on the Savoureuse. It is strongly fortified by Vauban, and has a population of 4400 persons, employed in various manufactures. Long. 6° 46' 40". E. Lat. 47° 38' 18". N.