Off topic, but I found a great resource. It's toward the bottom, but you will want to read my experience first.
I love Glacier National Park in Montana, though Mt. Rainier 100 miles from me has far more area of glaciers. And my best experiences there have been bicycle riding the "Going to the Sun" highway twice. It is a cyclists' dream throughout the US.
In 1997 our son David and I did a 5-day ride on almost every paved road in the park and into Canada to Waterton with Backroads, a commercial outfit. When we checked in with them at the Apgar campground - this was a camping trip - on a beautiful sunny afternoon, they informed us that they would be getting us up at 5:30 or 6 the next morning because all riders must be at the top before 11 am!! Furthermore, early the next morning I was greeted in the dark by on of the staffers telling me I had a flat tire to fix! It was a great ride. David took the van part-way, but not me. We enjoyed a sunny lunch at the top and hiked up the meadows for a mile or so; this was July, so the meadows were open. Then we zoomed down a great descent and along Upper St. Mary lake for another 20 miles. I remember during the descent thinking ""Someone is going to make this illegal because it is too much fun!"
In 2003 I celebrated my 58th birthday during an 803-mile bicycle ride from Elliot Bay in Seattle to Cut Bank, Montana. I also missed my 40-year high school reunion, since I was in Spokane, WA, on this ride. All the other riders wer from out of state and were very impressed by Washington - Stevens Pass, Leavenworth, the Columbia River Gorge, Lake Chelan, the Columbia again, Grand Coulee dam and Spokane's Riverfront Park. Sand Point Idaho and along "haning ears" lake. This route along the Clark Fork River avoids the 5500-foot pass that I-90 goes over at the Montana-state line. Up the Clark Fork to Trout Creek and Thompson Falls, Montana (yes, David Thompson had a trading post here). At Plain over a pass to one of my favorite areas - the large open valley that depressed Hot Springs, Montana, is in. To Flathead Lake, then Kalispell. It sure is beautiful in summer.
We reached Glacier Park after about 700 miles and had a rest day camping at West Glacier and some rain. Starting up the mountain - Going to the Sun - his was June, so there was snow everywhere! And snow melt crossing the highway in places that would be bone dry 2 weeks later. I was riding with a tiny Japanese-American woman from New York City. If she had been my wife I would have been shouting at her. Naturally enough when at the edge of the pavement it dropped off first 1,000, then 2,000 feet she was uncomfortable. So she rode in the center of the pavement, blocking traffic! Traffic wasn't that heavy, so I let her be.
As we got higher we had wind, then rain. We got to the top wet and cold. BTW we were early enough in the season that the 11:00 drop-dead hadn't taken effect yet, so we did this at a more reasonable time of day. At the top of Logan Pass we stumbled inside the visitor's center and it was about 3 degrees warmer than outside. BRRR. Then on to St. Mary at the east entrance to Glacier Park, which is one of my favorite spots. The descent wasn't nearly as much fun while freezing, just hoping to get lower, drier and WARMER.
Riding that mountain highway is an experience! And you can't take a photo that shows what it is like. Any photo just shows a tiny portion. Then you have to string several together and wave your arms... You just can't picture how huge the scene is.
This is the best I have found. The National Park Service has a Quiktime VR, which is a 360 degree photograph, that you scan around to get a feel for your self. This is up pretty high on the climb, but before the valley starts closing in toward the top.
Quicktime VR
Wow! It is around points of interest 7 and 8 on the map on
this page. Skip the links at the top. Go about 1/2 down the page for the map with labels.
And notice how the slope drops away over 1,000 feet to the valley floor. Now imagine how it feels riding a bicycle where you are higher than the guard rail and looking over it!! It's quite an experience. I hope to do it again.