While dark skies are unquestionably a huge advantage, you can get quite reasonable shots even in areas with moderate light pollution if you get very clear conditions.
I use the ClearDarkSky forecasts to check on atmospheric conditions, and usually find acceptable results with a seeing and transparency value of 3/5 or higher. It's interesting to see that this doesn't always happen when you've got an apparently clear night -- humidity and temperature can affect the visibility more than you might think.
Here are a couple of shots taken from Mount Baker National Forest, which is a good dark sky location, although the thin cloud on the horizon was highlighting distant lights more than ideal. As others have said, these might be considered overprocessed from a purely photographic standpoint, but they are quite popular!
Canon 5D Mark III, Canon 16-35mm f/2.8L II @ 16mm, ISO 6400, f/3.2, 30 second exposures, 11 shot panorama:
Canon 5D Mark III, Canon 16-35mm f/2.8L II @ 16mm, ISO 5000, f/2.8, 30 second exposures, 4 shot panorama:
The next two are taken from a park half-way between Vancouver and Whistler -- this is definitely not a dark sky location (it's about 30 minutes drive from Vancouver and 15 minutes from Squamish, a relatively large settlement), but the conditions allowed good visibility of the Milky Way:
Canon 5D Mark III, Canon 16-35mm f/2.8L II @ 16mm, ISO 8000, f/2.8, 45 second exposures, 5 shot panorama:
Canon 5D Mark III, Canon 16-35mm f/2.8L II @ 16mm, ISO 6400, f/2.8, 30 second exposure:
I'm still very much learning how to take these shots, so there is unquestionably a lot more that can be got out of the camera (and probably some more sympathetic processing that can be done, as well!) The most important thing is to get out there and try it -- don't think you need to drive half-way across the country, just try and find somewhere reasonably dark on a clear, moonless night and see what you can get!