Q: Where is Rental Car return at Union Station?
A: Union Station Parking Garage (101 H St NE, Washington, DC 20002)

As [MENTION=10054755]praveen_v[/MENTION] posted (oh, and welcome to FlyerTalk! - great first post), the entrance for rental car returns is a bit of a pain at Union Station.

FWIW, here are some shots from Google Maps & Street View as to what to look for:

1. Larger map view of Union Station, its parking garage and the specific ramp that you'll want to take boxed in red:


2. Larger aerial view of Union Station, the parking garage at the back and, again, the ramp you'll want to take boxed in red:


3. Zoomed in map view of the ramp and the turn lanes both east and west bound on H Street NE shown in blue:


4. Zoomed in aerial view of the ramp and the turn lanes both east and west bound on H Street NE shown in blue:


5. Street view on H Street NE and the ramp with the parking entrance boxed again in red - note that the far right lane is used for taxi waiting parking:


6. Street view on H street NE and the ramp with the parking entrance boxed again in red - this turn can be a pain at rush hour


7. Street view of the Union Station Parking Garage with correct ramp and entrance boxed again in red - the right set of ramp lanes are for taxis, etc.; sign for rental car return highlighted in yellow:


Good Luck!

David

p.s. Shots from Google Street View were probably taken on the weekend. During the week, this street can be busy - especially at rush hour