The ruins of an ancient Roman tomb hidden in the basement of a trendy clothing store.

Large collection from the 3rd millennium BCE.

This ancient Greek place of assembly and marketplace is being revealed layer by layer below the modern Athens cityscape.

Where commuters walk through remnants of an ancient Greek necropolis.

An ancient octagonal weather station named for the eight Greek gods of wind.

Step inside the first house designed by Catalan architect Antoni Gaudí, considered to be one of the first Art Nouveau buildings.

Gaudí's famously flamboyant architectural style is on full display in this sprawling park and garden.

One of Antoni Gaudí's most classic buildings is well-known for its "dragon-back" design.

Construction of Barcelona's iconic (but controversial) church is expected to be completed in 2026—a century after the death of its architect.

Portugal's National Pantheon has a history of curses, collapses and financial problems.

Ancient catacombs form the foundation for this Rococo orgy of a church.

This restored Portuguese cafe may well be the most beautiful place in the world to grab a Big Mac.

Elaborately carved to showcase the glorious wealth that the age of exploration brought to the Portuguese empire.

This Industrial Age architectural and engineering gem helps visitors and residents alike traverse Lisbon, “The City of Seven Hills.”

The stunning interior of this Gothic church is covered in ornate gold details.

A king's pet, a pope's gift, an artist's inspiration, and a tragic shipwreck.

An ancient and majestic fortress that played an integral role in Portugal's road to independence.

Legacy of the earthquake that nearly wiped Lisbon off the face of the Earth.

This unreal Portuguese palace looks as though it's made from a pile of different castles.

This eccentrically decorated palace is replete with grottoes, fountains, tunnels, and caves.

One of the most beautiful bookstores in the world hides a neo-Gothic interior behind an art nouveau facade.