Allegheny River in the context of "American paddlefish"

The Mississippi River System, also referred to as the Western Rivers, is a mostly riverine network of the United States which includes the Mississippi River and connecting waterways. The Mississippi River is the largest drainage basin in the United States. In the United States, the Mississippi drains about 41% of the country's rivers.

From the perspective of natural geography and hydrology, the system consists of the Mississippi River itself and its numerous natural tributaries and distributaries. The major tributaries are the Arkansas, Illinois, Missouri, Ohio and Red rivers. Given their flow volumes, major Ohio River tributaries like the Allegheny, Tennessee, and Wabash rivers are considered important tributaries to the Mississippi system. Before the Mississippi River reaches the Gulf of Mexico, it runs into its distributary, the Atchafalaya River.

In geography, a confluence (also conflux) occurs where two or more watercourses join to form a single channel. A confluence can occur in several configurations: at the point where a tributary joins a larger river (main stem); or where two streams meet to become the source of a river of a new name (such as the confluence of the Monongahela and Allegheny rivers, forming the Ohio River); or where two separated channels of a river (forming a river island) rejoin downstream from their point of separation.

Oakmont is a borough in Allegheny County, Pennsylvania, United States, along the Allegheny River. The population was 6,758 at the 2020 census. It is a suburb in the Pittsburgh metropolitan area. The borough is best known for the nearby Oakmont Country Club, a premier golf course that has been the site of numerous U.S. Open golf tournaments.

Allegheny County (/ˌælɪˈɡeɪni/ AL-ig-AY-nee) is a county in Pennsylvania, United States. As of the 2020 census, the population was 1,250,578, making it the state's second-most populous county, after Philadelphia County. Its county seat and most populous city is Pittsburgh, Pennsylvania's second most populous city. The county is part of the Greater Pittsburgh region of the commonwealth, and is the center of the Pittsburgh media market.

Allegheny was the first county in Pennsylvania to be given a Native American name. It was named after the Lenape word for the Allegheny River. The meaning of "Allegheny" is uncertain. It is usually said to mean "fine river". Some historians state that the name may come from a Lenape account of an ancient mythical tribe called "Allegewi" who lived along the river before being taken over by the Lenape.

The Monongahela River (/məˌnɒŋɡəˈhiːlə/ mə-NONG-gə-HEE-lə, /-ˈheɪ-/ -⁠HAY-), sometimes referred to locally as the Mon (/mɒn/), is a 130-mile-long (210 km) river on the Allegheny Plateau in north-central West Virginia and Southwestern Pennsylvania. The river flows from the confluence of its west and east forks in north-central West Virginia northeasterly into southwestern Pennsylvania, then northerly to Pittsburgh and its confluence with the Allegheny River to form the Ohio River. The river includes a series of locks and dams that makes it navigable.

Pittsburgh (/ˈpɪtsbɜːrɡ/ PITS-burg) is a city in Allegheny County, Pennsylvania, United States, and its county seat. Located in southwestern Pennsylvania where the Allegheny and Monongahela Rivers meet to form the Ohio River, it had a population of 302,971 at the 2020 census, making it the second-most populous city in Pennsylvania. The Pittsburgh metropolitan area has over 2.43 million people, making it the largest in the Ohio Valley and Appalachia, the second-largest in Pennsylvania, and the 28th-largest in the U.S. The greater Pittsburgh–Weirton–Steubenville combined statistical area includes parts of Ohio and West Virginia.

Pittsburgh is known as "the Steel City" for its dominant role in the history of the U.S. steel industry. It developed as a vital link of the Atlantic coast and Midwest, as the mineral-rich Allegheny Mountains led to the region being contested by the French and British empires, Virginians, Whiskey Rebels, and Civil War raiders. For part of the 20th century, Pittsburgh was behind only New York City and Chicago in corporate headquarters employment; it had the most U.S. stockholders per capita. Deindustrialization in the late 20th century resulted in massive layoffs among blue-collar workers as steel and other heavy industries declined, coinciding with several Pittsburgh-based corporations moving out of the city. However, the city divested from steel and, since the 1990s, Pittsburgh has focused its energies on the healthcare, education, and technology industries.

Point State Park (locally known as The Point) is a Pennsylvania state park which is located on 36 acres (150,000 m) in Downtown Pittsburgh, Allegheny County, Pennsylvania, US, at the confluence of the Allegheny and Monongahela rivers, forming the Ohio River.

Built on land that was acquired via eminent domain from industrial enterprises during the 1950s, the park opened in August 1974 after construction was completed on its iconic fountain. Pittsburgh settled on the current design after rejecting an alternative plan for a Point Park Civic Center designed by Frank Lloyd Wright.

Downtown Pittsburgh, colloquially referred to as the Golden Triangle, and officially the Central Business District, is the urban downtown center of Pittsburgh, Pennsylvania, United States. It is located at the confluence of the Allegheny River and the Monongahela River whose joining forms the Ohio River. The triangle is bounded by the two rivers.

The area features offices for major corporations such as PNC Bank, U.S. Steel, PPG, Bank of New York Mellon, Heinz, Federated Investors, and Alcoa. It is where the fortunes of such industrial barons as Andrew Carnegie, Henry Clay Frick, Henry J. Heinz, Andrew Mellon and George Westinghouse were made. It contains the site where the French fort, Fort Duquesne, once stood.