Each lung appears somewhat conical in shape with a rounded apex pointed upwards and a flat base directed downwards. The bases of the lungs rest on the convex domes of the diaphragm.

• The apex is the rounded upper tip of the superior end of each lung. It is situated above the superior thoracic aperture (thoracic inlet) posterior to the scalene muscles and above the first rib and clavicle. The apex of each lung is covered by the cervical part of the pleura and the suprapleural membrane.
• The base of each lung is broad, semilunar and concave. It lies on the thoracic (superior) surface of each diaphragmatic dome.

Besides the apex and the base, each lung has several surfaces and borders. Also, they contain fissures that divide the lungs into smaller sections known as the lobes. The lobes are further subdivided into bronchopulmonary segments.

Each lung has a pulmonary hilum through which various anatomical structures (major bronchi, blood vessels and nerves) enter and leave the lung via the root of the lung. All these anatomical structures of the lungs are described further in the following slides.