In humans the thigh is the area between the pelvis and the knee. Anatomically, it is part of the lower limb.
The single bone in the thigh is called the femur. This bone is very thick and strong (due to the high proportion of cortical bone), and forms a ball and socket joint at the hip, and a condylar joint at the knee.
The deep venous system of the thigh consists of the femoral vein, the proximal part of the popliteal vein, and various smaller vessels; these are the site of proximal deep venous thrombosis. The venae perfortantes connect the deep and the superficial system, which consists of the saphenous veins (the site of varicose veins).