The citadel occupies a strategic promontory overlooking the western approaches to the city, and its architectural composition reflects successive phases of military, political, and symbolic functions. The complex consists of massive stone walls, towers, and vaulted chambers, incorporating ashlar masonry of varying courses, with Herodian stones distinguishable by their characteristic drafted margins and bossed faces, while later additions exhibit Mamluk and Ottoman masonry techniques, including pointed arches, domed ceilings, and inscriptions. The citadel originally functioned as a defensive stronghold, controlling access to Jerusalem, and its towers—most notably the so-called Phasael, Hippicus, and Mariamne towers—demonstrate adaptations to contemporary siege warfare, with angular projections and reinforced corners. Over time, the Tower of David acquired ceremonial and administrative roles, serving as a garrison, a prison, and, in the Ottoman period, a symbol of municipal authority, thus exemplifying the layering of architectural forms and functions in a site of continuous occupation and strategic significance.

The round minaret is not part of the original complex, it was added much later in 1635 CE by the Turkish rulers. The citadel that stands today dates to the Mamluk and Ottoman periods. It was built on the site of a series of earlier ancient fortifications of the Hasmonean, Herodian-era, Byzantine and Early Muslim periods, after being destroyed repeatedly.

Biblical Era
As evidenced by the archaeological discovery of the Broad Wall, King Hezekiah was the first to fortify this area. The city's fortifications demonstrate that by the late eighth century the city had expanded to include the hill to the west of the Temple Mount. The motivation for building the walled fortification was the expected invasion of Judea by Sennacherib. The wall might be the one referred to in Nehemiah 3:8 and Isaiah 22:9-10.

Arab-Muslim Period
After the Arab conquest of Jerusalem in 638 CE, the new Muslim rulers refurbished the citadel. This powerful structure withstood the assault of the Crusaders in 1099 CE, and surrendered only when its defenders were guaranteed safe passage out of the city. In 1187 CE, Sultan Saladin captured the city including the citadel. In 1239 CE the Ayyubid emir of Karak, an-Nasir Dawud, attacked the Crusader garrison and destroyed the citadel. In 1310 CE the citadel was rebuilt by Mamluk sultan al-Nasir Muhammad ibn Qalawun, who gave it much of its present shape.

Ottoman Era
The citadel was expanded between 1537 and 1541 CE by the Ottoman sultan Suleiman the Magnificent, whose architects designed a large entrance, behind which stood a cannon emplacement. For 400 years, the citadel served as a garrison for Turkish troops.

Phasael Tower
The Phasael Tower, partially preserved in the Citadel of Jerusalem has been identified as either the Phasael Tower or the Hippicus Tower described by Josephus. Of the original tower itself, some sixteen courses of the original stone ashlars can still be seen rising from ground level, upon which were added smaller stones in a later period, which added significantly to its height. Herod named the tallest of the towers, 145 feet in height, the Phasael in memory of his brother who had committed suicide while in captivity.

al-Qala'a Mosque
Masjid al-Qala'a (مسجد قلعة داود) also known as the Masjid Qala'a e Dawud or Mehrab e Qala'a Daood is a small mosque located within the Qal'a (citadel) of Jerusalem, south of Bab al-Khalil (Jaffa Gate). First definitive mention of the mosque is from 1531-32 CE during it's reconstruction during the reign of Sultan Suleiman. The mosque is closed to public as of December 2015. It is one of the two mosques situated inside the Jerusalem Citadel.

Arab Fortification Tower?
During Muslim rule in the 8th century CE, a new citadel was established. The precise plan of this citadel is not known, as severe damage was caused when the Crusaders built their citadel. It was located in the south-eastern corner of the courtyard. Probably this tower stood at the corner of a new wall, which ran north and south. If we assume that the Arabs left the Hasmonean/Herodian wall as their western limit, the outlines of the Arab fort become clear.

Hasmonean/Herodian Remains
Remains of Hasmonean/Herodian era wall, which was strengthened by Herod and later rulers, runs north-east to south-west through the inner archaeological garden. This segment of the wall which surrounded Jerusalem during Hasmonean times (2nd century BCE runs through the courtyard. This wall was referred to as ”the First Wall” by Josephus Flavius and received its name as it was the first of three walls which surrounded Jerusalem during the Second Temple period. In Herod’s time and in the later Byzantine period, additions were made to the wall.

The Kishle
The Kishle was erected in 1834 by Ibrahim Pasha who governed the Land of Palestine from Egypt. It can be accessed from the dry moat which surrounds the Citadel or through a Crusader era hall in the Museum. Archaeological excavations have unearthed remains from as early as the 6th century BCE and walls from the time of King Herod as well as evidence from the Middle Ages. Of particular importance are the discoveries of a wall and other findings from the First and Second Temple Periods.

circa 1700 CE

Masjid Sayf
The small mosque, known as the Masjid e Sayf, is located within the Qal'a (Citadel ) of Jerusalem, along the southern part of the Citadel's eastern barbican. Sultan Suleyman I ordered a major restoration of the Citadel, including this mosque, in the early Ottoman period, as the mihrab bears the name of Sulayman al-Qanuni (The Lawgiver). Since the second half of the 16th century the mosque underwent some aletrations. In 1151 Hijri (1738 CE), it was restored by 'Ali Agha, the chief of the Janissaires in the Citadel.

The Tower of David Museum, situated within the medieval citadel at the Jaffa Gate, serves as the official historical repository for the city’s 4,000-year narrative. Reopened in June 2023 CE following a comprehensive $50 million renovation, the institution utilizes its unique archaeological setting—comprising Hasmonean, Herodian, Byzantine, Mamluk, and Ottoman stratigraphy—to exhibit and contextualize Jerusalem's significance to the three Abrahamic Faiths Judaism, Christianity, and Islam.

The museum features 10 new thematic galleries integrated into the citadel’s vaulted halls, employing interactive technology and archaeological artifacts to illustrate the city’s evolution from its Canaanite origins to the modern era. A focal point of the site is the Phasael Tower, whose Herodian base supports an observation deck offering a 360-degree panorama of both the Old and New City. In addition to its permanent chronological displays, the museum functions as a cultural hub, hosting contemporary art exhibitions and the Night Spectacular, a large-scale multimedia presentation projected onto the citadel’s ancient stone walls.