36,000 people live and work here. Like all ancient cities, it is composed of various quarters. It's quite difficult to get to the Dome of the Rock, the great Muslim religious site, the place to where Mohammed was miraculously transported overnight, according to believers.
Foreigners have to enter via a specific gate, and only within a one hour time slot. I was given various reasons for this, including that it is to prevent Israeli religious zealots from the far right from bombing the place - which I can believe - and that they are tunneling underneath to find the foundations of the Jewish Temple, so they don't want too many people walking about up above! This would be incredibly strange if it were true.
Later I read up on the modern history of the city - the ancient Moroccan district was completely razed in 1967, against all archaeological protests, and replaced with the modern Jewish district; so perhaps the tunneling theory is less bizarre than I first thought.