Trunk veins

Great saphenous vein (1), small saphenous vein (2)

Also known as saphenous veins or truncal veins. Each leg has two trunk veins, the great and the small saphenous veins. These important vessels of the superficial vein system lie slightly deeper in the connective tissue beneath the skin.
The great saphenous vein (Latin: vena saphena magna), formerly called the long saphenous vein, is the longest vein in the leg and runs up the inside of the leg from the medial malleolus of the ankle across the knee to the groin, where it empties into the deep vein system.
The small saphenous vein (Latin: vena saphena parva), formerly known as the short saphenous vein, runs from the outside of the ankle to just above the hollow of the knee, where it empties into veins of the deep vein system.

Incompetent valves in these superficial veins will cause trunk varicose veins.