In which US state is this located?

This is the famous Triple Crossing in Richmond, Virginia with three Class I railroads on separate levels.

Bottom level: the original Richmond and York River Railroad was extended after the American Civil War to connect with the Richmond and Danville Railroad, later part of the Southern Railway System, currently part of Norfolk Southern. The line runs east to West Point, Virginia.

Middle level: this was the main line of the Seaboard Air Line Railroad and is now part of CSX Transportation known as the "S" line, just south of Main Street Station. It is planned to become part of the Southeast High Speed Rail Corridor.

Top level: the Peninsula Subdivision Trestle is a long (4.8 km or 3 miles) viaduct parallel to the north bank of the James River built by the Chesapeake and Ohio Railway in 1901 to link the former Richmond and Allegheny Railroad with C&O's Peninsula Subdivision to Newport News and export coal piers.

The triple crossing has been a Richmond attraction for rail enthusiasts for over 100 years. It used to be unique. But in the early 2000s another triple crossing was constructed at the Santa Fe Junction in Kansas City, Missouri.