>>508600881 (OP)>Pretty crazy eh?actually no. this is common in a lot of places. If you want to redesign its easier to build on top of things, and sometimes parts of the old structure remain. They might also bring rubble in to fill the streets and raise them
You see this in a lot of both ancient and modern cities. Seattle is known for having the road raised literally an entire story, meaning basements were now two story basements and often they'd block them off because it turned into a mess of underground dens. There are cathedrals that started as small churches and over 1000 years build on top of 4+ times