Jakarta's Titantic 25-Mile Seawall

Shaped like Garuda, a bird-like national emblem of Indonesia, Jakarta's new seawall will cost a cool $40 billion. But it may be worthwhile. According to an article by Amy X. Wang: "Jakarta sinks an average of three inches a year, and parts of the coast are going down as much as 11 inches a year, according to geodynamic experts. Around 40% of the city is already below sea level."

"In an attempt to halt the damage, authorities are building a gigantic wall off the coast, measuring 25 miles (40 kilometers) long and 80 feet (24 meters) high, National Geographic reports. To fund the $40 billion and 30-year-long project, the city will also create 17 artificial islands, on which developers can build luxury homes, offices, and shopping malls."

The project isn't without controversy, including environmental concerns and accusations of corruption. The cause of the sinking might also be correctable: illegal groundwater extractions by citizens seeking fresh water.