Driving up if you don't stop is really quick--less than 10 minutes. But there are viewpoints along the way that you may want to stop at. We went during the day (not for sunrise or sunset) and spent about an hour walking the trails on the mountain. From the top you can see Bar Harbor and Bar Island and the Porcupine Islands as well as Schoodic Peninsula and the Cranberry Islands. There are signboards that tell you what you are looking at. The mountain is almost bare of vegetation which is something to see. This is more common farther north. My husband and I have visited Acadia probably about 25 times and Cadillac Mountain is our favorite! Enjoy!

If you have a rental car you don't provide any info, but if it's your vehicle you do. You can get more than one pass.

They are booked solid long in advance. We enjoyed our reservation so much that I looked to see if we could go again during the week we were there. Nothing available.

We saw sunrise in August. No charge. We arrived an hour before sunrise and had great parking. Tip-leave before crowd does or it may take a while to come back down.

I’ll answer my own question for anyone who’s wondering as well. I ended up going this Saturday (first Saturday in October). I had no issues getting in the mountain without a reservation before 4:30a. Rangers get there at 4:00a so I’d get there earlier to avoid any questioning. This may change is what the rangers told me, but right now they’re only enforcing reservations between 4:30-6:30, but not keeping people out outside of this time.

When you enter Mt. Desert Island you will be on Eden st (Rt 3) stay on the left, from there your only going to go a few miles and look for Eagle Lake Rd on the left as you enter Bar Harbor, then take another left onto Paradise Rd. that leds to Park Loop Rd. ~ finally there is one last left to turn onto Cadillac Summit Rd. Biggest tip is get ther about an hour before sunrise~ it truly gets packed quickly and parking goes onto the 2 lane road come closer to the time of the sunrise. Good luck and have fun ~ bring a blanket!

About 10 minutes from Bar Harbor and yes, there is lots of parking near the peak.

No you can not sleep in your car overnight there.