Its humdrum facade only adds to its electrifying appeal: a rooftop with panoramic views of a shapeshifting metropolis.

Home to more than 13,000 pieces of war memorabilia and military equipment.

The world's longest bridge fountain has hundreds of nozzles that create a beautiful, illuminated spectacle.

The deepest metro station in the world.

The remains of a 1st-century aristocratic Roman town house featuring beautiful well-preserved mosaics.