Ruins

This remnant of an ancient Persian city is considered to be the world's largest single-span brick vault arch.

The ruins of this medieval castle now stand as a monument against all wars.

The remains of a 19th-century school and living quarters are perched atop a mountain surrounded by a thick tropical forest.

A rare example of an ancient Japanese hill castle believed to be the fortress of a legendary demon.

Amalfi's pre-industrial history is slowly being engulfed by the lush vegetation of the Ferriere Valley.

The fragmented remains of a massive public bath connected to the city's water supply.

A colossal aqueduct from the second century B.C., deeply hidden in a gorge on the outskirts of Rome.

An abandoned village, frozen in time by the threat of a landslide.

This massive home was constructed by one of the greatest conservationists in Colorado history.

The only visible remains of this ancient Greek underground temple is its roof protruding from the earth.

This seventh-century fortification marked the western border of the Lombard duchy of Spoleto.

The ruins of this Roman temple dominate the small city in southern Lazio.

Once a bridge over the River Begej, now high and dry.

Only three columns survive from this ancient temple in the town of Cori.

An abandoned monastery sits on a far-off island in the Adriatic Sea.

Built in a perfect square, this archaeological site is one of the largest and best preserved ancient fortifications in India.

The ruins of an early-18th-century complex that could once house up to 12,000 horses.