The radial artery is the blood vessel that carries oxygen-rich blood in the forearm. You can feel the pulse of the radial artery by feeling the forearm just underneath the thumb. There are three arteries in the normal forearm that carry blood to the hand.

branch of the brachial artery beginning below the elbow and extending down the forearm around the wrist and into the palm

One of the main arteries of the arm, running down its full length into the hand. Arteries carry blood away from the heart.