At the end of L’Enfant Plaza in Southwest DC you will find a park dedicated to Benjamin Bannekar, who helped L’Enfant and Andrew Ellicott map out the city of Washington.
This little used, and unfortunately rather neglected, park is operated by the National Park Service. It was constructed in 1970. In 1998, Congress passed legislation that authorized a Bannekar memorial in D.C. This park was chosen for that memorial.