On the tibia, the soleus originates from the soleal line and adjacent medial border.
The ligament, which spans the distance between the attachments to the tibia and fibula, arches over the popliteal vessels and tibial nerve as they pass from the popliteal fossa into the deep region of the posterior compartment of the leg.
In the lower leg, the soleus muscle narrows to join the calcaneal tendon that attaches to the calcaneus.