 What would become DE 20 was originally an unimproved county road in 1920 , with the portion between Seaford and Concord under contract as a state highway . By 1924 , the road was completed as a state highway from the Maryland border east to Concord . The portion of road between Concord and Hardscrabble was proposed as a state highway a year later . By 1931 , the state highway was extended from Concord to Hardscrabble . A portion of what would become DE 20 west of Millsboro was built as a state road the following year . 
