10 Treasures We’ll Lose as Sea Levels Rise

Old Havana
A shot of the Havana Cathedral in Cuba. ToniFlap/iStock/Thinkstock

The last Cuban city founded by Spanish conquistadors in 1519, Old Havana retains much of its original character as both a large shipping port and military defense installation while offering visitors a vivid slice of life in the Caribbean's largest metropolis. The old city is tied together by five large plazas, each of which maintains its own character and personality. Old Havana features an array of Baroque and neoclassical architecture, exemplified by the private colonial mansions that line quiet side streets just off the main thoroughfares [sources: UNESCO, Rough Guides].

La Habana Vieja, as it's known to locals, is also home to some of the country's best museums and its lively arts scene. Thanks to a restoration initiative partially funded by the United Nations, the decaying city is getting a facelift and is poised to modernize its urban core, while retaining its old-world charm. That, of course, depends on Old Havana – as low as 7 feet (2 meters) above sea level at certain points – staying dry [sources: UNESCO, Rough Guides, Tablada de la Torre].