 Alexandria, VA | Floridian | Rockville, MD  |
| Amtrak Virginia: Northeast Regional | New Carrollton, MD | |
| Palmetto | ||
| Crescent | BWI Airport, MD | |
| Carolinian | Baltimore, MD | |
| Silver Meteor | ||
| Cardinal |
Washington, DC-Union Station Lower-Level platforms are located on the Western side of the station and consists of Tracks 22 through 28. Track 22 is presently closed as of 2025 and being reconstructed with a very modern-looking staircase, escalator, and elevator pavilion area under construction to lead down to it.
Tracks 23 and 24, 25 and 26, plus 27 and 28 all platform at three low-level island platforms that are mostly in the open air although the southern ends of the platforms are at the start of the covered interlockings that leads into the two track First Street tunnel. The platforms have a historic open-air trainshed over them. Tracks 23 and 24, along with 25 and 26 have elevator, two sets of escalators and a staircase leading up to the depot above. Access to tracks 27 and 28 that appears to only be used by VRE is a single short bridge from the Gate G headhouse that leads to an elevator, followed by an escalator and staircase down to the extreme end of this platform. This extra infrastructure is because this platform is shorter with interlocking switches beginning in the open air, not just under the station itself as the tracks converge into the tunnel.
There are two distinctive areas to enter the station. At the extreme southern end are three Amtrak Gate areas H through L. These are used by passengers boarding trains at these platforms (except for tracks 27 and 28). Just beyond this area is a wider area with escalators and stairs, this is the VRE waiting area, and area used by VRE passengers and as the area for passengers exiting from Amtrak trains. Some VRE trains are also announced as using the main Amtrak boarding gates.
These lower platforms are used by all trains coming to and from the station to and from Virginia, since the tracks immediately connect to the First Street tunnel just south of the station. This two-track over a quarter-mile long tunnel leads under First Street, along the edge of the United States Capitol, before curving slightly to the east (passing very close to the Capitol South Metro Station) and emerging onto an elevated viaduct just past New Jersey Avenue. The tunnel is not electrified although these tracks and platforms are fully electrified forming the southern end of electrified Northeast Corridor. The connection to this tunnel means these platforms are used by all Virginia Railway Express Trains on both the Fredericksburg and Manassas Lines.
The Lower-Level platforms connecting to Virginia means that all through Northeast Regional Trains to and from Roanoke, Newport News or Norfolk stops at the lower-level platforms. These platforms are also used by the long-distance Silver Meteor, Carolinian, Piedmont, Crescent, Cardinal, and Floridian. All through Amtrak trains, stopping at the station except for the Floridian undergo an engine swamp with Southbound trains having their electric ACS-64 Sprinter locomotives swapped for diesel P42 or Charger ALC-42 Locomotives.
Terminating Amtrak Northeast Regional (and Vermonter) trains can also use these platforms but because these platforms are all low-level so Acela Express trains can't stop here.
Photos 1 & 2: December 13, 2013; 3-34: July 15, 2014; 35-57: July 18, 2014; 58-85: September 23, 2015; 86-106: October 12, 2015; 107-122: September 2, 2023; 123 & 124: August 22, 2024; 125-131: May 8, 2025;
