The online encyclopedia Wikipedia continues its description of the typical circumstances in a slum:

“... many live in very narrow alleys that do not allow vehicles (like ambulances and fire trucks) to pass.”
(en.wikipedia.org/wiki/Slum)

The photo above was taken on Khan el-Zeit street, the main bazaar in the Old City of Jerusalem, on the eve of Eid Adha, the second-biggest yearly festival of Muslims.

The narrow bazaar was filled with as many people as potentially can fit there, and the pressure of the crowd squeezed the men and women into one huge collective hug (in a rather non-Islamic manner). There was simply not enough space to avoid bodily contact with everyone standing around you on all sides. The smaller children only survived thanks to the arms of adult men who were pushing other people aside, to create an empty space in the tightly-squeezed human mass.

The crowd moving an average of 10 or 15 meters per minute, it took 20 minutes for me to get to the nearest exit from this pedestrian traffic jam. This is not the perfect place to call an ambulance. A panic in the crowd, for example due to gunfire, explosions or an air-raid alarm, might easily cause a stampede where falling on the ground means death, children being the first ones to go down. (It has happened at western football stadiums, it keeps happening in Mecca... why should Jerusalem be an exception?)

The streets of the Old City are too narrow for the large crowds that Jerusalem attracts in holiday seasons. But why are the streets so narrow? The answer to this question is another sequel to the story of slums, building permissions, and a web of political and demographic reasons why things happen or don’t happen in Jerusalem. The following photo reveals one part of the mystery of the narrow streets:

What we see here is the Russian Orthodox Alexandrovsky Church, at the corner of Khan el-Zeyt bazaar and Suq el-Dabbagha street. Looking at the right side of the photo, we can see a slum extension added to the church building. This is where the narrow and crowded Khan el-Zeyt bazaar runs — originally designed to be much wider, when this church was built, but later filled with amateur architecture, which now serves as shops along the bazaar. (The owners of the church may not have been too happy when their building received this... uhm... modern eastern wing.)

The narrow alleys of the Old City are generally inaccessible by any other method of transportation than walking, so you can forget about wheelchairs, taxis, buses and underground trains. Walking the relatively long distances of the Old City can make you hungry, but fortunately there are numerous meat shops available, such as this one along Khan el-Zeyt bazaar: