In World War II the Russians were fighting along a 2,000-mile line that extended from the Black Sea to a point beyond the Arctic Circle. Arms and supplies from the United States and Great Britain came by convoy to the ice-free seaport of Murmansk, in the northernmost part of the Soviet Union. The route of the supply ships, which cut through the Arctic Sea, was so perilous that the seamen on the convoys often called it "Death Alley." The convoys, identified by the code initials "P.Q.," were in constant danger from Nazi submarines and planes. German forces based on the northern tip of Norway made daily attacks on the ships. One convoy in particular, the PQ-17, sustained enormous losses. Out of 37 ships, only 13 managed to reach Murmansk. Cargo totaling $700 million went down to the bottom of the Arctic Sea, but the real loss was in human lives.