Castel Sant'Angelo, Rome, Italy

The Castel Sant'Angelo was originally the tomb of emperor Hadrian and subsequent emperors until around ~400 AD, when it was turned into a fortress. Much of the fortress was destroyed and looted by the invading German tribes when they sacked Rome in 410. It was sacked again a hundred or so years later by another German tribe. Eventually it was used as the residence of the Popes, and even had an walled passageway connecting it to the Vatican City across the river. Now it is a museum where you can get nice views of Rome.

This is from the tower overlooking the Tiber river.

This is what the Mausoleum theoretically looked like.

They have some modern Italian military weapons.

Just the tip.

The inner circular structure has a wall.

Here's looking away from the Tiber.

On the roof with some cannons.

Here are some bocce balls.

Italians play with them in the park.

A view of the Ponte Sant'Angelo (Bridge of the St. Angel).

It goes across the Tiber.

Some Papal seal.

One of the angels.

One theory of the Castle's name was that it should be Castel Sant'Angle, because of the river bend. A papal typo caused the error which still propagates today.

Quite beautiful panoramas are possible from the tower.

More of the bridge.

The papal seal includes the keys of St. Peter.

Some church.

The Archangel Gabriel, sheathing his sword to announce the plague would end.

It is a legend that the pope had to destroy many of the pagan idols that once decorated the castle to convince the Archangel to intercede in the plague...