CONNELLSVILLE, a borough of Fayette county, Pennsylvania, U.S.A., on the Youghiogheny river, about 60 m. S.S.E. of Pittsburg. Pop. (1890) 5629; (1900) 7160, including 800 foreign-born; (1910) 12,845. It is served by the Pennsylvania, the Pittsburg and Lake Erie, and the Baltimore & Ohio railways, and by the interurban electric system of the West Penn Railway Co., which has a large power plant near Connellsville. Connellsville is the centre of the Connellsville coke district (in Fayette and Westmoreland counties), which has the largest production in the United States, the output in 1907 (13,089,427 tons) being 32·1% of that of the whole country. Connellsville coke is the standard grade. What is called the Lower Connellsville coke region lies in Fayette county S.W. of the Connellsville district. It is richest near Uniontown, and in 1907 produced 6,310,900 tons of coke, making it second only to Connellsville. The so-called Upper Connellsville (or Latrobe) district, near Latrobe, produced in 1907, 1,030,260 tons of coke. The combined output of these three districts in 1907 was 50·1 % of the total of the entire country. The borough of Connellsville has various manufactures including iron, tin plate, automobiles and various kinds of machinery; and a state hospital for the treatment of persons injured in mines is located here. Connellsville was first settled in 1770, was laid out as a town by Zachariah Connell, in whose honour it was named, in 1793, and was incorporated in 1806. The borough of New Haven (pop. in 1900, 1532) was annexed to Connellsville after the census enumeration of 1900.