A boulevard is a type of broad avenue planted with rows of trees, or in parts of North America, any urban highway or wide road in a commercial district.
Boulevards were originally circumferential roads following the line of former city walls.
In North American usage, boulevards may be wide, multi-lane thoroughfares divided with only a central median.
In France, it originally meant the flat surface of a rampart, and later a promenade taking the place of a demolished fortification.
It is a borrowing from the Dutch word bolwerk 'bulwark'.