Ironclads

In the mid-19th century, the British and French navies developed armored, steam-powered warships as a response to the rising use of explosive shells, which could burn through wooden-hulled ships.
With the outbreak of the American Civil War, the Union and Confederate navies rushed to build ironclad ships to counter each other. On March 9, 1862 the ironclads met in battle for the first time at Hampton Roads, Virginia. By the end of the war, the age of naval warfare between wooden ships was at a close.