Nothing to do with King David
The Tower of David (also known as the Jerusalem Citadel) at Jerusalem’s Jaffa Gate has nothing to do with King David. The name of the area was given to the site by the Byzantines who, as successors to the Romans, ruled the land of Israel until the Muslim invasion in 638 CE. The Byzantines erroneously thought the site is where King David built his palace. They got the name "Tower of David" from the Song of Songs, written by King Solomon, David’s son, who wrote: "Thy neck is like the Tower of David built with turrets, whereon there hang a thousand shields, all the armor of the mighty men." The name has stuck ever since.
What we see today is a Mameluke structure built in the 13th century and enhanced by the Ottoman Turks in the 16th century. The main tower is built on top of one of King Herod’s city towers which in turn was built on top of a Hasmonean structure, of which remnants of both can be seen today. King Herod ruled from 37 BCE to 4 BCE, the Hasmoneans from 140 BCE until Herod. Archeological finds in the citadel go back more than 2500 years!
The Tower of David houses a museum inside its walls which give a clear time line to the various rulers of the city from the Canaanites until the British Mandate. Using maps, videotapes, holograms, drawings and models, the exhibit rooms each depict Jerusalem under its various rulers. It’s a great way to start a tour of Jerusalem in order to get a good overview and understanding of sites in the city. One can also climb up the ramparts and get great views of the new and old cities.
What most people don't know, including those who have already visited the Tower of David Museum, is that about a year ago the museum opened up the moat surrounding the citadel and the nearby Kishle Prison to the public. The moat has an interesting history of its own. Originally dug out by the Crusaders the moat reveals a Second Temple period mikve (ritual bath) and the steps leading down to the swimming pool of Herod's palace! The moat was filled in, dug up, used as a garbage dump and paved as a road for a Prussian Kaiser's entrance among other things.
Kishle prison is on one side of the moat. Built to hold prisoners in the 1880's by the Egyptian ruler, Muhammad Ali, the building laid abandoned since the Six Day War. Archeologists dug deep down under the floor and what they found is amazing to see. There are layers from the Ottomans all the way back to drainage systems for Herod's palace in the Second Temple period and even the remains of the city walls from the time of Hezekiah in the First Temple period. This is a real rarity in this part of the city. For those who want to see it all in Jerusalem this is site is a must.