The Chellah or Shalla (Berber languages: Sla or Calla; Arabic: شالة),[1] is a medieval fortified Muslim necropolis and ancient archeological site in Rabat, Morocco, located on the south (left) side of the Bou Regreg estuary.

By the mid-14th century Marinid sultans had enclosed a part of the site with a new set of walls and built a religious complex inside it to accompany their mausoleums.

[2] Jean Boube, who led some of the modern excavations at the site, discovered neo-Punic artifacts dating as far back as the 3rd century BC, which suggests there must have been a small trading post here around that time.

[12]: 170 One of the two main Roman roads in Mauretania Tingitana reached the Atlantic through Iulia Constantia Zilil (Asilah), Lixus (Larache) and Sala Colonia.

The port of Sala (now disappeared) was used by commercial Roman ships as a way station on their southwestward passages to Anfa and the Insula Purpuraria (Mogador island).

[20][21] After the end of the Umayyad Caliphate in Al-Andalus in the early 11th century, the Almoravids assumed control of the region and built a new ribat at the mouth of the river.

[24][22] The Almohad caliph Abu Yusuf Ya'qub al-Mansur (r. 1184–1199) also began construction of a vast new royal city with new walls on the site next to ancient Sala, corresponding to what is now the historic center of Rabat, but it was never finished.

[19] During the Marinid period the site of ancient Sala was re-appropriated and turned into a royal necropolis for the ruling dynasty, now known as Chellah (Arabic: شالة, romanized: Shāllah).

[6] The first Marinid constructions and the first royal burial were in 1284–85, when sultan Abu Yusuf Ya'qub chose the site to bury his wife, Umm al-'Izz.

[5] Construction of the main gate was finished by Abu al-Hasan, as evidenced by an inscription on it which dates its completion to July 1339 (Dhu al-Qadah 739 AH) and refers to the complex as a "ribat".

Abu Inan may have also been responsible for building or completing the madrasa (Islamic college) and the prominent minaret that adjoin the mosque and mausoleums.

[6][25] Remains at the site today also show that the necropolis was accompanied by a residential quarter to the north, complete with a water supply system.

Between 1360 and 1363 Ibn al-Khatib, the vizier of the Nasrid sultan Muhammad V, visited the site during his master's exile from Granada and mentioned it in his writings.

[29] Legends about buried treasures also led to illegal excavations at times and pushed authorities in the 20th century to move some of the most important objects in the necropolis to museums in Rabat.

[25] The first excavations of the Roman city were carried out in 1929–30 under the supervision of Jules Borély, head of the Service des Beaux-Arts, an agency of the French Protectorate in Morocco at that time.

This initial work cleared away vegetation from the ruined mosque and unearthed a large portion of the "monumental" Roman quarter visible today.

[33][34][35] The excavated portion of the Roman city covers about 1.2 hectares and corresponds to the "monumental" district around the forum, where the most important public buildings stood.

Jean Boube dated the temple to the mid-first century BC, which would make it a Mauretanian structure (before the region was annexed as a Roman province).

Statues of the Mauretanian client kings Juba II and Ptolemy have been found here, leading Boube to suggest the temple was originally dedicated to them.

The upper level was the temple proper, consisting of single cella and a pronaos (vestibule chamber), elevated on a podium and surrounded on three sides by a portico of 32 columns.

[12]: 165–166 The other major building in this western area is located directly opposite the capitolium, to the south and near the perimeter wall of the Marinid religious complex.

At its center is a large octagonal opening, with niches set along its interior walls, that corresponds to an underground nymphaeum that once extended further up to the ground level of the building.

[5] Most of the Marinid structures inside are contained within a religious complex in the southeastern part of the enclosure, called the khalwa (Arabic: خلوة).

[38] The pool was originally the latrines and ablutions facility of the 13th-century mosque, but at some point it became submerged due to water seeping in from underground and it is now inhabited by eels.

[6][38] The back wall inside the mausoleum has a central double-arched niche framed by an epigraphic frieze containing verses 30 and 31 of Surah XVI from the Qur'an.

[38] These two friezes enclose a central rectangular zone filled with sebka decoration above three blind polylobed arches with small colonettes.

Its main shaft has a traditional square base and its four facades are each decorated with a sebka composition above two blind polylobed arches (each enclosing small windows).

[6][38] In addition to Abu al-Hasan's mausoleum, one of the most exceptional examples of decoration in the complex is the gateway that leads towards the madrasa from the forecourt on the north side of the mosque.

The decoration of this gateway also has similarities to the gate of the Sidi Boumediene Complex in Tlemcen (present-day Algeria), suggesting that the same team of artisans may have been involved in both designs.

The changing room consisted of a central square space flanked by two small rectangular galleries divided from it by a row of arches supported by columns.