The section of Calle Restauración to Calle Colón that runs along side Plaza España down to the old ship yards (las atarazanas in Spanish) in the Colonial Zone. It was one of the main streets where all the ships were loaded and unloaded at the Puerta de las Atarazanas of Santo Domingo.
To see what the area looked like many years ago visit page 4 of the Old Pictures of Dominican Republic page.
For the exact location check the Map of the Colonial Zone around numbers 31 and 88