You'll find the little birds tucked within the rocks of this Australian beach.

Once housing children next to hardened criminals this historic jail once displayed Ned Kelly's skull until it was stolen.

An expansive complex of subterranean tunnels is all that remains of one of Europe's most formidable medieval fortresses.

These spartan apartments are provided to clergymen visiting Vatican City.

The Vatican's secret porn-festooned bathroom was painted in erotic murals by one of the greatest artists of the Renaissance.

This equestrian statue of Constantine the Great has been the subject of criticism for centuries.

This park on the outskirts of Rome boasts two ancient Roman aqueducts and a medieval tower.

A huge enchanting public park just outside the ancient walls of Rome.

Rome's ancient Etruscan rival, now a park full of ruins.

A mysterious chasm in the heart of the ancient Roman Forum, the Lacus Curtius was once believed to be a gateway to hell.

This Roman arch marks the location of an ancient gate at one of the Seven Hills of Rome.

The ruins of the largest gladiatorial school in Rome are largely hidden under modern streets.

Ancient ruins hidden underneath a modern luxury hotel.

The commemorative stone column conceals a secret laboratory.

The grounds of this Jacobean estate contain one of the oldest mulberry trees in England.

The ritual has been performed uninterrupted for nearly 700 years.

A quiet, semi-secret square with statues of Mahatma Gandhi, Virginia Woolf, and a conscientious objectors stone.

These official units of measurement—including chains and perches—lie hidden beneath tourists' feet in a popular London hub.

Ship-sized kinetic sculptural fantasy.

Lovers proclaim their unbreakable bond by leaving their names on locks fastened onto the Shoreditch fence in East London.

The Columbia Road Flower Market is now open every Sunday, rain or shine.

A student driver's nightmare.

The sumptuous ceiling was one of the last things Charles I saw before his execution.

There's an exclusive Beefeaters pub hidden in the Tower of London.