The Persian Corridor is the name for a supply route through Iran

Iran

Iran , officially the Islamic Republic of Iran , is a country in Southern and Western Asia. The name "Iran" has been in use natively since the Sassanian era and came into use internationally in 1935, before which the country was known to the Western world as Persia...

 into Soviet Azerbaijan

Azerbaijan SSR

The Azerbaijan Soviet Socialist Republic , also known as the Azerbaijan SSR for short, was one of the republics that made up the former Soviet Union....

 by which British aid and American Lend-Lease

Lend-Lease

Lend-Lease was the program under which the United States of America supplied the United Kingdom, the Soviet Union, China, Free France, and other Allied nations with materiel between 1941 and 1945. It was signed into law on March 11, 1941, a year and a half after the outbreak of war in Europe in...

 supplies were transferred to the Soviet Union during World War II.
Note: The nation of Iran has been referred to as "Persia" in the West since the time of the Persian Wars. The earliest Iranian peoples known to recorded history are the Parsua mentioned in an Akkadian

Akkadian language

Akkadian is an extinct Semitic language that was spoken in ancient Mesopotamia. The earliest attested Semitic language, it used the cuneiform writing system derived ultimately from ancient Sumerian, an unrelated language isolate...

 text.