In 1991 Germany closed a finished but not operational power plant in Kalkar[0]. Nowadays it's a theme park built by Dutch entrepreneur Hennie van der Most, who is famous for these kinds of projects. I've visited the plant as a kid with my dad and uncles when it was open for public but barely any work had been done on the demolition or transforming into a theme park. For me it was the most awesome theme park I ever visited. You could go into the control room and press all the (buttons), look inside the reactor, see all the technology that went inside this plant, peruse the entire complex and visit almost every building as almost nothing was off limits except for what was used by the park staff for office/storage. I still regret not having a camera at that time to capture everything I saw. Nowadays it's 'just' a theme park with an all-in formula.

[0] https://en.wikipedia.org/wiki/SNR-300