An aqueduct is a water supply or navigable channel (conduit) constructed to convey water. In a more restricted use, aqueduct (occasionally water bridge) applies to any bridge or viaduct that transports water-instead of a path, road or railway-across a gap. Large navigable aqueducts are used as transport links for boats or ships.

In architecture, a crypt is a stone chamber or vault beneath the floor of a church usually used as a chapel or burial vault possibly containing sarcophagi, coffins or relics.

The agora, translatable as marketplace, was a public space and an essential part of an ancient Greek polis or city-state. An agora acted as a marketplace and a forum to the citizens of the polis.