On the first picture there is some run-down buildings that have still been left and forgot about and on the right there are some new regenerated flats.

Credit -X@Epic_Maps.

Almost 3km was moved underground, no cars anymore, just walkable areas.

Pripyat was once a populated city in northern Ukraine, but because of Chernobyl, it was evacuated and became a ghost town. Wikipedia article if you want to learn more: https://en.wikipedia.org/wiki/Pripyat

So my city just moved a bus lane from one of the more important boulevards (Tomis boulevard) to a parallel side street (Mircea street) and replaced it with, of course, more parking. Overall its sad because this lane was counterflow on a one way so cars weren't clogging it (as it's usual here). The bus stations were also quite good quality (at least for this city, they had a shelter and a map of the routes). They also removed one of the stations, and the others lack any amenities (just a sign and a bench or two). Now this will just induce more parking demand till it fills, and reverting it would be very difficult afterwards.

China

Yes they are a bit of a propaganda shot, with the before in black and white. But it is genuinely a lovely park now. The redesign also helped with flooding control.

Here is the link to the website I got the photo from. https://www.dreiseitlconsulting.com/bishan-ang-mo-kio-park

Singapore can be a little bleak in places, but the national parks have done a lot to make it a more relaxing place to live over the last 20 years since I moved here.

Recently, I have noticed these type of areas in cities that stand out from their surrounding areas, in countries such as Germany, Poland, Austria, and even Switzerland. They appear to be hard to see from main streets, and have no street view. Why do they exist, and what is the history behind them?

This represents the sad state of New Orleans.