About 100m (300 ft.) west of Jemaa el Fna is Marrakech's most prominent landmark, the Koutoubia Mosque. Its towering minaret is visible for miles in any direction and is the focal point from which the French laid out the road network in their ville nouvelle. The name, meaning the Bookseller's Mosque, reflects the honorable trade that used to be practiced in a nearby souk.
The mosque was constructed, and reconstructed, in the 12th century by the Andalusian-conquering Almohad dynasty and lies on the site of a former Almoravid mosque. It was this prior occupation by the Almoravids, whom they considered heretics, that likely spurred the Almohads to build a new, "pure" mosque rather than renovate the existing structure. Unfortunately, someone got the measurements wrong, and the mosque was not correctly oriented toward Mecca -- indicated inside the prayer hall by the mihrab, or prayer niche. Even though worshipers can correct this directional problem when commencing prayer, the Almohads decided to build a second, correctly aligned mosque alongside the original. Both buildings were constructed during the reign of Abdullah el-Mumin (1130-63) and existed side by side until the older structure eventually fell into disrepair.
Standing on the mosque's esplanade with your back to Jemaa el Fna, the ruins of the original are visible to your right. The existing mosque's principal feature is its 13m-wide (43-ft.) and 68m-high (223-ft.) minaret, completed by el-Mumin's grandson, Sultan Yacoub el Mansour (1184-99). This is the oldest and most complete of the Almohad's three great towers -- the others are the Tour Hassan in Rabat and the Giralda in Seville, Spain -- and was considered the blueprint for all future Moroccan-Andalusian architecture. Given a cleanup for the beginning of the new millennium, the tower is especially stunning when floodlit each night. Note: As with most Islamic places of worship in Morocco, the interior of the mosque is off-limits to non-Muslims. If you happen to be traveling on the Tizi n'Test road in the Western High Atlas between Marrakech and Taroudannt, stop off at the visitor-friendly Tin Mal Mosque from which the Koutoubia was modeled.