Oak Ridge, the Secret City

[BeTheGoddess]

Oak Ridge sister city in Russia, Obninsk:

The history of Obninsk began in 1945 when the First Research Institute Laboratory "V", which later became known as IPPE (Institute of Physics and Power Engineering) was founded.
On June 27, 1954, Obninsk started operations of the world's first nuclear power plant to generate electricity for a power grid. The city was built next to the plant in order to support it.

https://en.wikipedia.org/wiki/Obninsk

And one of THEIR sister cities in China, Mianyang:

Mianyang is home to the CAEP and Science City, an immense Military Research Complex which was the site of the development of China's first nuclear bomb.

https://en.wikipedia.org/wiki/Mianyang

This was not really what I was expecting to read, but there is plenty here to learn...