This trail should be about 13 miles but turned into 15 for me because during my exploration of the summit, I found that when you walk out of the main gate when the observatory is closed for business, you get locked out. Not to worry, took the vehicle toll road down which is to your left as you exit the gate. This adds approx 1.5-2 miles of easy down hill on mostly paved road until you're able to connect back to the Mt Wilson Trail. This was a long trek and hard. I took lots of short breaks and adding that extra mileage was kind of a bummer. I'll still do this again so that I can find the sign at the top. I did not know where to find the sign and should have done more research. I generally know where it is now after reading some AllTrails reviews. There were patches of snow closer to the summit, I'd say about the last 1.5 miles to the summit, you get more patches of snow but passable without any special equipment, just being careful.

I went on a weekday and there was really very few people on the trail. Streams/water was flowing in many places as well as a spout at the summit to refill. Cosmic Cafe was closed.