It depends on other traffic/parkers, but there is a downtown parking garage about a hundred yards from one edge of the sanctuary. That can be a pretty good bet if closer spots are filled.

RV parking is available in the West End.

There are no tours, the JDS is a park and open space it is free and open to all.

Dawn until Dusk

There is a multi story public car park next to the park.

I would suggest contacting Willie Hoevers, who is also making plans for the 20th anniversary of John Denver's death. Willie is also on Facebook. My wife Diane tells me she knows you from Facebook. We live up in Wisconsin.

I didn't see any access control so would believe it is open year round. You would miss all the gardens but the stone would still be there.

There is no charge, it is an open, public park

Yes, it is outdoors along a walking path. Dogs are allowed in the entire area. Please be respectful of the area. Doggie pick-up bags are located at each end of the walkway so please grab one before you enter. The sanctuary has many large rocks with his lyrics etched on them. Smaller rocks are in the area too for sitting. You can also just walk through and spend as much time as you need.

The answers already given about public transportation are valid. There is a bus from Denver, a delightful but slow train service, and a private bus service. It's about 150 miles to Denver from Aspen.