40.21, -75.37
Montgomery County, colloquially referred to as Montco, is a county in the Commonwealth of Pennsylvania. As of the 2020 census, the population of the county was 856,553, making it the third-most populous county in Pennsylvania after Philadelphia and Allegheny counties.The county seat and largest city is Norristown. The county is part of the Philadelphia–Camden–Wilmington PA-NJ–DE–MD metropolitan statistical area, known as the Delaware Valley, and marks the Delaware Valley's northern border with the Lehigh Valley region of eastern Pennsylvania.
The county borders Philadelphia, the nation's sixth-largest city, to its southeast, Bucks County to its east, Berks and Lehigh counties to its north, Delaware County to its south, and Chester County to its southwest.
The county was created on September 10, 1784, out of land originally part of Philadelphia County. The first courthouse was housed in the Barley Sheaf Inn. It is believed to have been named either for Richard Montgomery, an American Revolutionary War general killed in 1775 while attempting to capture Quebec City, or for the Welsh county of Montgomeryshire, which was named after one of William the Conqueror's main counselors, Roger de Montgomerie, since it was part of the Welsh Tract, an area of Pennsylvania settled by Quakers from Wales.