In 1638 Shah Jahan shifted the Mughal Empire's capital from Agra to Delhi. A new royal palace known as Red Fort or Red Fort Delhi (Lal Qila) was constructed. It was begun in 1639 and completed in 1648. The name Red Fort comes from the massive red sandstone walls that surround it. The Red Fort has walls extending up to 2 kms. in length with the height varying from 18 mts. on the river side to 33 mts. on the city side. The Red Fort Delhi has two main entrances, the Delhi Gate and the Lahori Gate. The latter faces Chandni Chowk, the city's most crowded but diverse market. The Red Fort also houses the Diwan-i-Aam or the Hall of Public Audiences, where the Emperor would sit on a marbled paneled alcove, studded with gems, and hear complaints of the common people. The Diwan-i-Khas or the Hall of Private Audience, where private audiences were granted. This hall is made of marble, and its centre-piece used to be the Peacock Throne, which was studded with rubies and gems. Today, although the Diwan-i-Khas is only a pale shadow of its original glory, yet the verse of Amir Khusro " If there is Paradise on the face of earth, it is here, it is here, it is here" reminds us of its former glory. The Rang Mahal or the 'Palace of Colours' as it is known, holds a spectacular Lotus shaped fountain, made out of a single piece of marble, and housed the Emperor's wives and mistresses. The other attractions enclosed within this monument are the hammams or the Royal Baths, the Shahi Burj, which used to be Shahjahan's private working area, and the Moti Masjid or the Pearl Mosque. Even today, the Red Fort (Lal Qila) is an eloquent reminder of the glory of the Mughal Empire.