Foramen magnum

The structures passing through the foramen magnum are:

Anterior Part:      1. Apical ligament of dense.
                            2. Vertical band of cruciate ligament
                            3. Membrana tectoria

Subarachnoid Space:

1. Vertebral artery
2. Ant. Spinal artery
3. Post. Spinal artery
4. Spinal accessory nerve.
5. Sympathetic plexus around vertebral arteries.

Posterior part:  1. Lower part of medulla.
                         2. Meninges.