Langdon Park Outdoor Pool Mills Ave & Hamlin St Ne Washington, DC 20018 Phone : (202) 576-8655 Business Category Swimming Pools Amusement & Recreation Parks And Recreation Department Of--outdoor Pools, Langdon Park Mills Avenue & Hamli Washington, DC 20001 Phone : (202) 576-8655 Business Category Government Offices-Federal Government Offices-City Village & Twp Government Offices State & Local Government Offices & Public Schools