The south gate is the main entrance for the public. It is now called Amar Singh Gate, which was originally known as Akbari Darwaza as William Finch, an English traveller who visited India between 1608 and 1611 has recorded. It was renamed as such about the middle of the 19th century by the British. Distorting the episode of 1644 when Rao Amar Singh, elder son of Gaj Singh, the Rathor chief of Marwar and then a Mughal Mansabdar, assassinated Mir Bakhshi Salabat Khan and violated the sanctity of the Mughal Court and was himself cut to pieces. The British made a torso of a stone horse and fixed it near the Gateway and circulated the story that Amar Singh escaped alive with his horse which jumped over the ramparts across the moat and was converted into a stone sculpture. The gateway was renamed Amar Singh Gate accordingly, which later became popular among the masses.
The plan of this Gate is identical to that of the Delhi Gate and it also has a drawbridge over the moat. The mam entrance viz. the Hathi Pol has an open space at the Delhi Gate but here it is given a magnificent court with colonnades overhanging it. It is more adequately protected than the Delhi Gate. But the bastions of the Akbari Darwaza are smaller and less ornately finished. Their lower portions are divided into oblong and arched panels that are covered with glazed tiles in beautiful geometrical designs in blue, green, yellow and white colours. The panels of the upper parts are plain. Each bastion is covered by a chhatri made of heavy piers instead of slender pillars, a circular chajja and with an inverted lotus hemispherical cupola. The cupola was originally decorated with glazed tiles, whose remains are visible at some places.
After entering the barbican of the southern Gate, one faces a tall multi-storeyed Gate of red-sandstone on the eastern side. It has a small pointed arched entrance. The Gate is built over a high plinth with a rectangular small platform supported on stone brackets. The arch is outlined by white marble inlay work of geometrical design.
The surface of the Gate is flanked by two arched panels decorated with marble inlay. There are square panels on both sides over which there is a long rectangular panel with six small holes over which are three loopholes of temple shikhar design with a parapet of wide flame design.
The interior of the Gate has colonnades with a rectangular super structure with parapet merlons. The quadrangle has arcades with series of arched spaces, super-imposed by series of colonnades.