The Avenue of Mausolea is a series of grand palatial tombs.

The world's second-tallest flagpole stands proud despite dropping rank.

The first version of this stalwart construction appeared around 3,000 years ago.

This dark, damp, perilous tunnel is the only passage from north to south Tajikistan.

The remains of an ancient city-state along the Silk Road.

This remote, abandoned Soviet observatory promises spectacular views for those who can reach it.

Where the father of Persian poetry is laid to rest.

This medieval citadel once guarded the western entrance of the Pamir Highway.

This ancient Silk Road outpost overlooking the Wakhan Valley is miraculously still standing.

The largest dam in the world and the site of a potential disaster.

This 100-foot tall tombstone memorializes victims of 40 years of nuclear testing in Kazakhstan.

Stelae-eyed stones greet visitors to a corner of Kirov Park.

At 72 feet below sea level, it's the lowest commercial airport in the world.

This Soviet statue is based on a piece of propaganda that's been elevated to national myth.

A sober museum housed in the original administrative building of one of Stalin's largest gulags.

This was once the largest city in Kazakhstan, and a major stop on the Silk Road.

This Soviet-era athletic and recreation facility is the highest ice skating rink in the world.

A Stalinist prison camp for the wives and children of men accused of betraying the Soviet state is now a memorial museum.

Local lore says this 700-year-old tree has sacred and medicinal properties.

Avenue of trees planted by cosmonauts before their space departures.

An entertainment center in a huge transparent tent.

The remains of a monument in the remote Kazakhstani desert dedicated to the only men to die in outer space, the crew of the Soyuz 11 rocket.

One of the most horrible legacies of the Cold War is a site where the Soviet Union tested nuclear bombs on civilians.

Nicknamed Kazakhstan's Grand Canyon, this natural wonder lies east of Almaty near the Chinese border.