The Romans were extracting stone from the quarry located in the modern neighborhood of Tašmajdan, using it for the building of Singidunum, and for many surviving sarcophagi. An aqueduct used to conduct water from the modern Kumodraž area. At some point it was joining the aqueduct from the Mokri Lug and then continued further to the castrum. Both Mokri Lug and Kumodraž are hills, so the natural inclination allowed for the water to flow downhill to Singidunum. The modern area of Cvetkova Pijaca was a location of three additional water systems. Aqueducts passed through the modern center of Belgrade, Terazije, and the main pedestrian zone, Knez Mihailova Street, which was one of the main access roads to the city and today still follows the original Roman street grid.