What is the longest vein in the human body?

The great saphenous vein is recognized as the longest vein in the human body, extending from the foot all the way up to the groin. It runs along the length of the leg, traveling up the medial side, and drains into the femoral vein near the groin area. Its length is significant, typically measuring around 40 cm to over 50 cm in adults, depending on individual anatomy and variations. This vein plays an important role in venous return from the lower extremities back to the heart.

In contrast, the femoral vein, while a major vein in the thigh that carries blood back toward the heart, is not as long as the great saphenous vein. The popliteal vein is located behind the knee and is shorter, collecting blood from the lower leg into the femoral vein. The inferior vena cava is a large vein that carries deoxygenated blood from the lower half of the body to the heart, but it is a large vessel rather than a single vein running the length of a limb. Hence, the great saphenous vein holds the title of the longest vein in the body.