Those with a sharp eye can find the hidden image of a German Shepherd on the memorial's Mural Wall.

A three-story tower of books about Abraham Lincoln is one of the more unusual monuments to the president.

The innocent intentions of this monument are somewhat lost in the sculpture's muscled imagery.

The oldest building in the District of Columbia was preserved because of a mistaken connection to George Washington.

This seemingly out-of-place gas station by the Watergate hotel was once described as the most expensive gas station in the world.

A gorgeous mural outside a beloved D.C. restaurant pays homage to famous Black Americans.

A bar, burger joint, and arcade housed in a late 19th-century church building.

A room hidden behind a swinging shelf in the children's section.

The Corinthian columns that towered over Abraham Lincoln’s inauguration stand proud.

The haunting "Hell House Altar" is one of the few remnants of an abandoned college that has been a magnet for local legends.

This centuries-old gothic monster has been converted into a sprawling, glossy bookstore.

A once-magnificent collegiate church is falling into ruin.

This Roman statue is missing a limb from when the Venetians stole it from Constantinople during the Crusades.

This palatial spiral staircase was so unusual the name "snail" was given to the noble family who built it.

Go inside to really appreciate this 500-year-old technological masterpiece.

This community on a small Venetian island has taken to painting their houses in bright neon hues.

This private skyway is filled with art and was expanded explicitly so that Hitler could appreciate a river.

A large grotto built in the 16th century amidst Florence's famous Boboli gardens.

Over 50 exquisite hand-painted Renaissance maps decorate a Medici storage room.

One of Catholicism's four major basilicas has a series of papal portraits that are said to predict the end of the world.

2300-year-old Roman road connecting the empire.

Breathtaking and huge 430 year old maps of Italy.

Historic fortifications form the boundary of Vatican City, but it’s not entirely surrounded by walls.

Brass cobblestones mark the places where individual Holocaust victims were taken from their homes.