pres erved ▁assemb lage ▁of ▁late ▁ 1 9 th ▁century ▁resident ial ▁architecture ▁and ▁work mans hip ▁in ▁the ▁Dup ont ▁Circle ▁Historic ▁District . ▁The ▁particular ▁historic ▁value ▁of ▁this ▁the ▁block ▁was ▁highlight ed ▁when ▁the ▁National ▁Park ▁Service ▁expanded ▁the ▁Dup ont ▁Circle ▁Historic ▁District ▁in ▁ 1 9 8 4 . ▁In ▁arg uing ▁for ▁the ▁expansion , ▁the ▁D . C . ▁Historic ▁Pres ervation ▁Office ▁described ▁the ▁block ▁as ▁a ▁" be aut iful ly ▁preserved ▁enc lave ▁much ▁pra ised ▁for ▁its ▁original ▁st ained ▁glass ▁and ▁brick ▁and ▁co pper ▁work ." ▁ ▁The ▁front ▁fac ades ▁of ▁the ▁homes ▁at ▁the ▁eastern ▁end ▁of ▁the ▁row ▁have ▁orn ate ▁angular ▁roof ▁lines ▁typical ▁of ▁the ▁Queen ▁Anne ▁style . ▁Also ▁notable ▁are ▁the ▁co pper - cl ad ▁b ays ▁and ▁Hum mel st own ▁stone ▁trim ▁from ▁the ▁Leb anon ▁Valley ▁in ▁Pennsylvania . ▁The ▁eight ▁houses ▁between ▁ 1 6 1 0 ▁and ▁ 1 6 1 8 , ▁and ▁ 1 6 1 3 ▁and ▁ 1 6 1 7 ▁were ▁built ▁beginning ▁in ▁April ▁ 1 8 8 9 . ▁The ▁five ▁homes ▁at ▁the ▁western ▁end ▁of ▁the ▁row ▁( 1 6 3 4 ▁to ▁ 1 6 2 6 ) ▁form ▁a ▁distinct ▁unit ▁and ▁were ▁built ▁in ▁ 1 8 9 3 . ▁They ▁have ▁essentially ▁similar ▁designs ▁in ▁the ▁less ▁orn ate ▁Roman es que ▁rev ival ▁style , ▁differ ing ▁from ▁each ▁other ▁only