Tracking Snowden's world tour
In May, former National Security Agency contractor Edward Snowden left the U.S. from Honolulu to Hong Kong
Snowden spent several weeks in Hong Kong, during which he initially revealed his identity.
While the U.S. sought to extradite Snowden from Hong Kong, the Chinese did not detain him and he was able to fly from Hong Kong to Russia.
Snowden has been staying in the transit area of Sheremetyevo, Moscow's main international airport, since June 23.
Since the U.S. has revoked his passport, he is unable to leave the airport until another country provides him with travel papers.
Several South American countries are among the best candidates for granting Snowden asylum
However, most flights to Havana, Snowden's most likely stopover before heading onward, involve crossing through U.S. airspace, where the plane could be grounded, searched and Snowden would likely be arrested.
Bolivia, Nicaragua and Venezuela have all said they would accept Snowden. France, Italy, Portugal and Spain last week blocked Bolivian president Evo Morales' presidential jet, believing Snowden was aboard.
Though getting to those countries while avoiding the airspace of nations which would likely ground his plane would involve taking a route staying over the ocean for longer than is normally deemed safe.