Segovia's most recognisable symbol is El Acueducto (Roman Aqueduct), an 894m-long engineering wonder that looks like an enormous comb plunged into Segovia. First raised here by the Romans in the 1st century CE, the aqueduct was built with not a drop of mortar to hold together more than 20,000 uneven granite blocks. It's made up of 163 arches and, at its highest point in Plaza del Azoguejo, rises 28m high.
It was originally part of a complex system of aqueducts and underground canals that brought water from the mountains more than 15km away. Its pristine condition is attributable to a major restoration project in the 1990s. For a different perspective, climb the stairs next to the aqueduct that begin behind the tourist office.