Which U.S. Navy dry dock was attacked at Pearl Harbor on December 7, 1941?

Dry Dock Number 1 was attacked during the Japanese raid on Pearl Harbor on December 7, 1941.

The dry dock contained USS Pennsylvania, the flagship of the U.S. Pacific Fleet, along with the destroyers USS Cassin and USS Downes. Japanese bombs damaged the ships and the dock area during the attack's second wave.

Cassin and Downes were badly damaged when fires and explosions spread through the dock. Their condition looked catastrophic, but both destroyers were later rebuilt using salvaged machinery and other components. Pennsylvania suffered damage but remained afloat.

Dry Dock Number 1 was part of the Pearl Harbor Naval Shipyard, whose repair facilities were strategically important. The Japanese attack therefore targeted not only ships at their moorings but also the maintenance infrastructure needed to keep the Pacific Fleet operating.