There was a query in the forum (see link at end of article) regarding travel from Casper to Gillette. I spent some time looking up information and thought I would share the information with everyone headed for Gillette. Among the resources a site that gives information and pictures on routes all across the US. There is also a reference specifically for the Wyoming DOT which seems to have an excellent and informative site that allows you to query any road in Wyoming for alerts, current conditions and frequently pictures of what the road looks like. Sometimes multiple pictures of current conditions along the road.
I have run your off-interstate trip through my Garmin Topo Map and it shows a distance of 134 miles starting elevation at Casper of 5165 feet which goes to a maximum of 5698 feet in the first 19 miles. From there, elevations are up and down but the maximum slopes seem to be on the order of 120 feet per mile. The second climb goes from 4893 feet to 5490 feet in 10 miles to give you an average 60 feet per mile but there are stretches in there where you will reach 120 feet per mile. From there it is downhill to 5038 feet and then right back up to 5455 feet, a change of 417 feet in 7 miles or about 60 feet per mile again and there are once again stretches where you will approach 120 feet per mile in that section. The remaining 66 miles are pretty much downhill to an elevation of 4590 feet at Gillette. There is one short climb and just before you reach Gillette but that pretty much describes the elevations.
We're coming from the south and will leave I-25 at Douglas and take 59 all the way. The distance is 114 miles and it looks pretty much similar to your route. From 4841 feet at Douglas we will climb to 5363 feet in the first 10 miles, 53 feet per mile on average. We will descend to 4641 feet and in the next 32 miles we'll climb to elevations near 5069 feet four times, Two of those climbs are about 430 feet and two are less than 200 feet. The end of our trip will have a descent to 4527 feet and the short climb just before reaching Gillette.
I checked AARoads for information on Highway 59. It indicates that 59 is a desolate road from Douglas to Gillette. It also indicates that recent coal and natural gas development in the Powder River Basin (well north of Gillette) has increased the truck traffic on this road and bills it as one of the busiest roads in Wyoming along the stretch from Garner Lake Road to Gillette which is north of Gillette and should be of no concern to us coming in from the south. There are photos on this site as well though most of them are in Douglas. The one rural photo is from north of Gillette but it looks like good quality road with miniscule shoulder. Go to the home page for AARoads Home to look up other roads throughout the US.
Another resource I found with a Bing search on the internet is the Wyoming DOT. Here is the search page where you can enter the road and get current conditions and some pictures if available.
Looking at this information, if you like the wide-open west, you will love this route!
Here is the latest update: Having just completed the trip up Highway 59 I can say that the scenery is very nice, Thunder Basin National Grasslands are in the area, we saw many pronghorn antelope, very few houses. There were trucks, not a huge amount but we were passed by a dozen or so from Douglas to Gillette. We do travel around 60 to 65 and truckers always want to pass a motor home. The road was good, a few rough bridge joints but the surface is fine. No shoulder and few passing areas until you are north of the junction with 387. Coming in from the south, Garner Lake Road takes you right to the fairgrounds but there is road construction. No problems driving, just one lane and a 30 MPH speed limit.
We are in Gillette with the Monaco International Pre-Rally. The facilities are nice, grounds look good and we're looking forward to some nice weather and a fun Pre-Rally. Hope to see lots of you soon.
Source: Casper to Gillette