The day after I went exploring the churches in Bethlehem, I again hired a taxi for the day and went all over the place in Palestine. This time, I went to Jericho to explore a couple of archaeological sites. The first site I visited was Tell es-Sultan, or Sultan's Hill. This is an archaeological site showing the earliest settlement in Jericho, which dates about 8000 BC. It definitely gives the term Old City a new meaning.
As you can see, this is primarily a dig site. There were still archaeologists doing their job there when I visited. There are a few signage, so most of this is left to the visitors' imagination. There is a short video that the authorities play before you visit, which helps a little bit in visualizing what this site might have looked like ages ago.
I think this is probably the oldest man-made structure I have visited. The megalithic temples in Malta which I have visited only date around 3000 BC, which is about 4000 years younger than this one. Anyone who has a strong interest in archaeology should definitely visit this place. It's fascinating.