A borough of Allegheny county, Pennsylvania, U.S.A., on the Allegheny river, about 20 m. N.E. of Pittsburg. Pop. (1890) 4627; (1900) 5472 (11 73 being foreign-born); (1910) 74 1 4. Tarentum is served by the Pennsylvania railway and by an electric line connecting with Pittsburg. Among manufactures are plate glass and bottles, table ware, paper, bricks, iron and steel articles, and steel sheets and billets. Coal mining is an important industry, and the borough is supplied with natural gas. Tarentum was first settled in 1796, was laid out in 1829 at the direction of Henry Marie Brackenridge (1786-187,), 2 who by marriage had come into possession of the site, and it was incorporated as a borough in 1842. The first glass manufactory was established in 1872.