Alcatraz Island is quite small: it’s about 22 acres in area, which is roughly 9 hectares or 0.09 square kilometers.

Quick Scoop

  • Area: about 22 acres (≈ 9 hectares / 0.09 square kilometers).
  • Length: around 1,675 feet (about 511 meters) from end to end.
  • Width: about 590 feet (around 180 meters) at its widest point.
  • Highest point: roughly 135 feet (about 41 meters) above the water.

To picture it, 22 acres is in the ballpark of 16–17 American football fields placed together, so Alcatraz is compact but big enough to have held a full prison complex, lighthouse, military structures, and open yards.

Information gathered from public forums or data available on the internet and portrayed here.