The citadel of Jerusalem, known as the "Tower of David," has been a landmark of the city since ancient times. The citadel is located on the western side of the Old City, just south of the Jaffa Gate. Its location was chosen for topographic reasons this is the highest point of the southwestern hill of Jerusalem, higher than any other point in the ancient city, including the Temple Mount. A series of fortifications built here in the course of more than twenty centuries, protected Jerusalem from the west and also overlooked and controlled the entire city.

A first archeological survey of the citadel, and excavations, were conducted between 1934 and 1947. Renewed excavations were undertaken after the reunification of the city, between the years 1968 and 1988, preparing the opening of the site to visitors.

Every period has left its mark and has been identified in the assemblage of architectural remains. In the citadels foundations are buried the remains of Jerusalems fortifications from the end of the monarchic period (8th to 6th centuries BCE) through the early Arab period (seventh to eleventh centuries). The outline of the citadel known today is from the Crusader period; the citadel itself was built in the mid-16th century by the Ottoman sultan Suleiman the Magnificent, and incorporates the remains of earlier citadels dating from Ayyubid and Mamluk times.

The Citadel is protected by a high wall and large towers, and it is surrounded by a wide, deep moat, part of which was blocked in modern times. The entrance is from the east, via an outer gate, a bridge over the moat and a fortified inner gate house.

In the citadels courtyard, excavations have revealed the remains of fortifications dating from the late monarchic period to the Hellenistic and Roman periods. Here was the northwestern corner of the First Wall which is described in great detail by the contemporary Jewish historian Josephus Flavius. According to him, the First Wall extended from here towards the Temple Mount to the east and also to the south, surrounding Mount Zion and then joining the southern wall of the City of David. (War V,4,2) Remains of this wall and of three large towers are preserved to an impressive height of over 7 m. in the citadel courtyard. Several construction phases belonging to different periods can be observed, distinguishable by differences in the masonry and in the method of laying the stones.

The wall was first built in this area by Hezekiah, king of Judah, at the end of the 8th century BCE. A detailed description of its construction on the eve of the Assyrian invasion of Judah, is in the Bible: He [Hezekiah] set to work resolutely and built up all the wall that was broken down and raised towers upon it, and outside it he built another wall. (2 Chron. 32:5) The remains of that incredibly wide wall (ca. 7 m.!), built of large boulders, were uncovered at great depth on the bedrock of the hill. This mighty fortification protected a new residential quarter built on the southwestern hill of Jerusalem which, until that time, comprised only the City of David and the Temple on Mt. Moriah. The wall was damaged in 587/6 BCE, when Jerusalem was conquered by the Babylonians.

The dimensions of the Tower of David are approximately 22 x 18 m., consisting of 16 courses of large ashlar stones weighing over a ton each. They have trimmed margins and a flat central boss, carefully laid without gaps, and the interior of the tower is filled with large ashlars. The Tower of David is one of the most impressive examples of royal construction of the Second Temple period in Jerusalem. It stands to this day to a height of 20 m.!

The three towers built by Herod and the other fortifications created a powerful, well protected fortress. Thence the decisive strategic role it played in the First Jewish Rebellion against Rome (66-70 CE) which ended with the siege of the city, its conquest and destruction. This is attested to in another tower, located in the southern part of the citadel, which was built in the 1st century CE and was destroyed during the rebellion: a thick layer of debris, including stones, plaster, and charred wooden roofing beams, was uncovered.

After the destruction of Jerusalem in 70 CE, the Romans established a camp to quarter the Tenth Legion on the southwestern hill of the city. It was protected by the three towers built by Herod, which the Roman commander Titus had ordered to be left intact. (Josephus, War VII,1,1) Remains of this Roman Legion camp were uncovered in the courtyard of the Citadel; they include clay water pipe sections bearing seal impressions reading "LXF," for Legio X Fretensis, the full name of the Tenth Legion.

During the Byzantine period, the fortifications of the citadel, including the Tower of David, were restored. Nearby, monks built monasteries and other religious institutions, as reported by several contemporary Christian travelers. Only fragmentary remains of fortifications, walls, cisterns and a lintel engraved with a cross, date to this period.

In the 8th century, during the period of Arab rule over Jerusalem, a new citadel was established. Among its remains are a rounded corner tower measuring 10 m. in diameter, from which 4-m. thick walls extend to the north and to the west. The precise plan of this citadel is not known, as severe damage was caused when the Crusaders built their citadel.

The Crusader citadel, built in the 12th century, was innovative and extended northward and westward, beyond the ancient city wall. The early city wall became an inner terrace wall in the courtyard, which was buried under some 10 m. of debris, protecting and preserving it until its exposure during the archeological excavations.

Today, for the first time in its long history, the citadel is no longer used for military purposes. Instead, it functions as the museum of the history of Jerusalem. Presented in its various towers are exhibits tracing 5,000 years of the citys history. In the courtyard, remains of the First Wall and its towers, of the Second Temple period and of the fortification from the Byzantine and early Arab periods, have been preserved and serve as a veritable guidebook to the long history of Jerusalems fortifications on the southwestern hill.