This is the Zeche Zollverein in Essen, in the Ruhrgebiet area in NRW, Germany.
Its was active as a hard-coal mine from 1851 until 1986. One of the most productive mines worldwide for a long time of its existence, 240million tons of coal were mined in its active time and up to 8000 people at once worked there (600.000 in its whole active time combined). its shafts reached up to 1000 meter deep into the ground.
Also part of the zeche zollverein is a coking plant, active from 1961 until 1993, turning up to 10000 tons of coal to coke per day in 304 ovens. It also produced things like ammonia, raw benzene and tar as side products.
It was tranformed for recreational use and nowadays the area is used for some museums, exhibitions, concerts, lots of events and a lot more cultural activities. Additionally a lot of mine shafts, equipment & machinery are kept intact and can be visited through guided tours.
Source for most of this (and if you want to read more about it): https://www.zollverein.de/zollverein-unesco-world-heritage-site/
And the wonder is called "ruhr valley", fitting as zeche zollverein is one of the most well known places of the ruhrgebiet.