The i-95 doesn't travel through the District of Columbia, rather; the i-95
travels around the outskirts of DC.
In the DC area, the i-95 mostly travels
mostly through the state of Maryland - which travels around the eastern
outskirts of DC.
In the DC area; the i-95 mostly follows the same route as the i-495 ... where
they both travel around the eastern portion of DC in a semi-circular pattern -
north & south.