The shoreline of Havana is a rocky plateau on the outside of the sea wall, or Malecon. Malecon is also the name of the wide street inside the sea wall.
The sea wall was started by U.S. Army Corp of Engineers during the United States' occupation after the so-called Spanish-American War (really a war for control of Cuba) in 1898. The crumbling buildings along the Malecon are now being restored by the Spanish. Having no money for these types of projects, Cuba receives aid from many foreign sources these days, with the notable exception of the United States.
Click here or click here for other views of the Malecon.