<P> The Washington City Canal , completed in 1815 in accordance with the L'Enfant Plan , travelled along the former course of Tiber Creek to the Potomac River along the present line of Constitution Avenue , NW ( formerly B Street , NW ) and south around the Capitol , thus defining the northern and eastern boundaries of the Mall . Being shallow and often obstructed by silt , the canal served only a limited role and became an open sewer . The portion of the canal that traveled near the Mall was covered over in 1871 for sanitary reasons . </P>
<P> The Washington City Canal , completed in 1815 in accordance with the L'Enfant Plan , travelled along the former course of Tiber Creek to the Potomac River along the present line of Constitution Avenue , NW ( formerly B Street , NW ) and south around the Capitol , thus defining the northern and eastern boundaries of the Mall . Being shallow and often obstructed by silt , the canal served only a limited role and became an open sewer . The portion of the canal that traveled near the Mall was covered over in 1871 for sanitary reasons . </P>
when was the national mall in washington dc built
when was the national mall in washington dc built
1815
1815