Only the most intrepid urban explorers cross the tattered ruins of the old Iron Curtain to endure the excessive bureaucracy, military paranoia and freezing winds of the East to hunt for the ghosts of an empire. Rebecca Litchfield is one who couldn’t resist the haunting allure of the ruins of the Soviet Union.

Dr. P.A. Smithe was sent by the American Red Cross as a doctor and surgeon to work at a hospital in Vienna. He sailed to Europe in December 1915 and returned home in August 1916, according to his daughter, who donated his images to the National World War I Museum. Photo: Turkish army, including cavalry, infantry and artillery. (Photo by Dr. P.A. Smithe/National World War I Museum, Kansas City, Mo.)

Jorge, an immigrant from Mexico, dressed as the Sesame Street character Elmo rests in Times Square, New York July 29, 2014. Elmo and Cookie Monster have long delighted young viewers on TV's “Sesame Street”, but the recent antics of New York street performers dressed as the beloved characters have drawn the ire of city officials and now the show's producers. Sesame Workshop, which owns the rights to Big Bird, Ernie and the assorted puppet monsters on the 45-year-old program, said on July 29, 2014 it was drafting plans to stop performers who dress up as the characters from appearing in Times Square, where they pose for photos with tourists and then demand tips. (Photo by Eduardo Munoz/Reuters)

A tourist poses for a picture with the Sphinx at the Pyramids of Giza in Cairo, Egypt, on October 19, 2011. (Reuters/Jamal Saidi)

A Virgin Atlantic passenger plane flies in the sky with the moon seen in the background, in London, Britain January 19, 2016. (Photo by Toby Melville/Reuters)

A man rides a horse at a playground on a hill in Kabul April 19, 2015. (Photo by Mohammad Ismail/Reuters)

Participants wearing masks during a hazy day at the Beijing International Marathon in front of Tiananmen Square, in Beijing, October 19, 2014. (Photo by Reuters/Stringer)

Rag pickers collect recyclable material at a garbage dump in New Delhi November 19, 2014. (Photo by Ahmad Masood/Reuters)