One of Europe's greatest attractions, the stunningly beautiful Calat Alhambra (Red Castle) is perhaps the most remarkable fortress ever constructed. Muslim architecture in Spain reached its apogee with this pleasure palace once occupied by Nasrid princes and their harems.

With a sombre exterior, the true delights of this Moorish palace are within. The tour begins in the Palace of the Nasrids - the main council chamber where the sultan's chief ministers met. The largest of these chambers was the Hall of the Mexuar, which Spanish rulers converted to a Catholic chapel in the 1600s. Then comes the Golden Room and the Patio del Mexuar. Constructed in 1365, this is where the sultan sat on giant cushions and listened to the petitions of his subjects or met privately with his chief ministers. The windows here are surrounded by panels and richly decorated with tiles and stucco. The Palace of the Nasrids was constructed around two courtyards, the Court of the Myrtles and the Court of the Lions. The latter was the royal residence. Behind it is the Hall of the Ambassadors with an elaborately carved throne room that was built between 1334 and 1354. The crowning cedar wood dome of this salon evokes the seven heavens of the Muslim cosmos.

An opening off the Court of the Myrtles leads to the greatest architectural achievement of the Alhambra, the Court of Lions, constructed by Muhammad V. At its center is Andalusia's finest fountain, which rests on 12 marble lions. These marble lions represent the hours of the day, the months of the year, and the signs of the zodiac. Legend claims that water flowed from the mouth of a different lion each hour of the day. This courtyard is lined with arcades supported by 124 slender marble columns. This was the heart of the palace, the most private section where the sultan enjoyed his harem, which included both male and female beauties.

Next is the Sala de los Abencerrajes, named for a noble family who were rivals of the last emir, Boabdil. To get rid of his rivals, Boabdil invited them to a banquet. In the middle of the banquet, his guards entered and massacred the guests. Other salons have stories of intrigue - the Hall of the Two Sisters where the sultan kept his "favourite". Eunuchs guarded the harem but not always well. According to legend, one sultan beheaded 36 Moorish princes here because one of them was suspected of being intimate with his favourite. 

The nearby Hall of Kings was the great banqueting hall of the Alhambra, site of parties, orgies, and feasts. Its ceiling paintings are on leather and date from the 1300s. A gallery leads to the Court of the Window Grill where Washington Irving lived and wrote his famous book Tales of the Alhambra. The best-known tale is the legend of Zayda, Zorayda, and Zorahayda, the three beautiful princesses who fell in love with three captured Spanish soldiers outside the Torre de las Infantas.

The Royal Baths have lavish decorations in many colors. Light enters through star-shaped apertures. To the immediate east of the baths is the Daraxa Garden and the sultana's private balcony looking over Granada. Next comes the the beautiful kitchen garden, once filled with milling servants preparing the sultan's banquets. These gardens are dominated by the Ladies' Tower. This tower and its pavilion, with its five-arched portico.

Finally comest Emperor Charles V's Palace. This Holy Roman emperor built a Renaissance palace in the middle of the Alhambra. Charles V did not consider the Nasrid palaces grand enough so, in 1526, he ordered a student of Michelangelo to design him a fitting royal residence within the Alhambra. In spite of its incongruous location, the final result is one of the purest examples of classical Renaissance in Spain. The square exterior opens to reveal a magnificent circular two-story courtyard that is open to the sky. Inside the palace is Museo de la Alhambra displaying artefacts including fragments of sculpture, unusual braziers and perfume burners used in the harems.

Outside the Alhambra's southern foundations is the Generalife, built in the 13th century and set on 30 lush hectares. The sultans used to spend their summers in this palace safely locked away with their harems. The Generalife was meant to be a retreat from the Alhambra. The highlight of the Generalife is its gardens, begun in the 13th century but much modified over the years. Originally, they contained orchards and pastures for domestic animals. Highlights include the Water Staircase, an enclosed Oriental garden constructed around a long pool, with rows of water jets making graceful arches above it.