Pittsburgh ( (originally )) is the second largest city (after Philadelphia) in the Commonwealth of Pennsylvania with a population of 312,819 in 55.5 sq mi. The population of the eight-county metropolitan area is 2,462,571. The city averages 5,636 people per sq mi and has an urban oriented job market ranking 6th in the nation for jobs within the urban core. Pittsburgh is the county seat of Allegheny County, which has a population of 1,281,666. Downtown is built on a triangular tract where the Allegheny River and Monongahela River meet to form the Ohio River. The skyline features 151 high-rise buildings,"High-rise Buildings of Pittsburgh" 446 bridges,Pitt Chronicle: "Venice, Schmenice" two inclined railways, and a pre-revolutionary fortification. Pittsburgh is known colloquially as "The City of Bridges" and "The Steel City" for its many bridges and former steel manufacturing base.

While the city is historically known for its steel industry, today it is largely based on healthcare, education, technology, robotics, fashion, and financial services. The city has made great strides in redeveloping abandonded industrial sites with new housing, shopping and offices, such as the SouthSide Works. While Pittsburgh faced economic troubles in the mid 1970s as the steel industry waned, modern Pittsburgh is economically strong. The housing market is relatively stable despite a national subprime mortgage crisis, and Pittsburgh has added jobs in 2008 even as the national economy is in a significant jobs recession. This positive economic news is in contrast to 30 years ago when Pittsburgh lost its manufacturing base as those jobs moved offshore.

In 2007, Forbes Magazine named Pittsburgh the 10th cleanest city, and in 2008 Forbes listed Pittsburgh as the 13th best city for young professionals to live. The city is consistently ranked high in livability surveys. In 2007, Pittsburgh was named "America's Most Livable City" by Places Rated Almanac.

Etymology

main: Name of Pittsburgh

Pittsburgh was named in 1758 by General John Forbes in honor of the British statesman, Sir William Pitt. Given that Forbes was a Scotsman, some speculate the intended pronunciation of the settlement was "Pittsburra", similar to the pronunciation of Edinburgh. It was incorporated as a borough in 1794 and chartered as a city in 1816.

Pittsburgh was officially named with its present spelling on April 22 1794, by an act of the Pennsylvania Department, stating, "Be it enacted by the Senate and House of Representatives of the Commonwealth of Pennsylvania, in General Assembly met, and it is hereby enacted by the authority of the same, that the said town of Pittsburgh shall be, and the same is hereby, erected into a borough, which shall be called the borough of Pittsburgh for ever."