The Old City is the heart of Jerusalem, and for many, the center of the world. The walls surrounding today's Old City were built by the Ottoman Sultan Suleiman in the 1500s--but in certain spots you can see remnants of walls from King Herod's time.
The Old City contains places holy to Jews, Christians and Moslems so you'll feel the special spiritual atmosphere that hovers over the city. Don't miss any of the fascinating museums (Tower of David Museum of the History of Jerusalem; Old Yishuv Court Museum; Wohl Archaeological Museum); archeological sites (the Southern Wall excavations, Western Wall Tunnels) or opportunities for some intense bazaar shopping and bargaining in the Moslem Quarter and along the Cardo.
Take time to wander through the alleyways and back streets of all the quarters to get a feel for the incredible diversity of people who live and pass through Jerusalem. Stop in at some of the smaller churches and synagogues you'll find tucked away in courtyards where worshipers have been coming for centuries, and don't forget to stop for some fresh-squeezed juice, hummus or felafel as you try to take it all in.