Peter Jackson's crew made a great work portraying the Mines of Moria in their movies. If you want to see something eerie similar in real life, you can visit one of the original 12 Unesco World Heritage Sites, namely the Wieliczka salt mine near Krakow, Poland
The mine has been operational in one form or another since the neolithic age and the current organisation running it claims to have over 700 years of continuos history.
The site itself is 327m deep and it takes around three hours to explore just the casual tourist route. More experienced travellers can opt to have a real journey in the dark organised by a guide. Nikolaus Copernicus and Johann Wolfgang von Goethe both visited the depths 500 and 200 years ago respectively.
It's not just the site being a mine that makes it dwarven but rather the huge halls with spiralling, gravity-defying staircases, lavishly decorated with sculptures and reliefs chiseled by the miners themselves. In the parts open to public there are also medieval machines reconstructed for further reference.
Note that I took the pictures during a casual trip, some 90 meters below ground with mining lamps being the only source of light.