Mill Valley, CA: how dark is the sky here?

Mill Valley's sky measures rural here. Little local light dome. Most stars are visible; the Milky Way is faint but often findable away from town lights. That's brighter than 11.4% of the 3,206 US cities in this dataset.

This comes from a satellite measuring light radiating upward, not a person's eyes on the ground, so it isn't the same as a Bortle class, though the two track each other closely.

How far Mill Valley is from a meaningfully darker sky

161 miles from Mill Valley, straight-line, sits Truckee, CA, the nearest city here with a darker sky than Mill Valley's own rural band.

Truckee, CA is itself still a measured city, not a designated dark-sky park, this only compares against the 3,206 places this dataset covers.

How Mill Valley compares nationally

Mill Valley, CA has a population of about 13,904, one of 3,206 US cities of 10,000 or more residents in this dataset. Mill Valley places 365 of 3,206 cities in this dataset's darkest-to-brightest order.