OHLAU, or OLAU, a town of Prussia, province of Silesia, government of Breslau, on the right bank of the Ohlau and left of the Oder, 18 miles S.E. of Breslau. It has a large castle, several churches, an orphan hospital, and a poor-house. There are extensive tobacco manufactories and a flour-mill, besides breweries, distilleries, &c. Pop. 6079.