CO state parks fill up quickly. If you haven't already made reservations, do your homework on when you can reserve, and be online the moment reservations open - not two hours later, but the minute reservations open. June will be busy. Camping in CO has exploded in recent years.
I've stayed at Golden Gate Canyon, and it's gorgeous. If you like to gamble (I don't) Blackhawk and Central City are just down the road. Don't miss Garden of the Gods when you're in CO Springs.
As for Moab in June, you'll be hot...about mid 90's. Be prepared for heat. If possible, find places that have at least 30 amp hookups, or bring a 3500 watt generator. https://www.accuweather.com/en/us/mo...weather/336126
You'll very likely need your AC.
As ependydad said, its dusty and dry in the west...more than you can imagine.
I can't tell where you live, but altitude can be an issue for some. Time in CO Springs will allow for acclimation, but going from 5280 to 9500 is a dramatic change.
Drink LOTS of water, because it will not only help oxygenate you and help stave off altitude sickness, it will also help you cope with dehydration...a real problem in the mountains and the desert. It's dry up here. If all of you adapt well, great. If not, don't dilly-dally at altitude. It takes hours to get over a mountain pass, and many are at least 11,500 feet.
The top of Loveland Pass (I-70) has several tunnels. If you run propane to keep your fridge cool, you must stop and shut off the propane to go through the tunnels. There are places to pull over, but be prepared.
Watch out for rock falls. They are rare, but every year a number of drivers get crushed by rocks the size of houses. https://www.codot.gov/news/images/i7...ll-012813/view
More importantly, rocks the size of chairs and basketballs fall regularly and line the shoulders of roads.
It's unlikely you'll encounter this, but many roads in CO have no guardrails protecting from 800 foot drops. Again rare, but much different from roads elsewhere. This one's famous. https://www.dangerousroads.org/north...ghway-usa.html
and see the photo of Million Dollar Highway below. These are the exception, not the rule, but lack of guardrails IS
the rule...you may be shocked if you're accustomed to driving in the East (I moved here from NY).
Many sites in CO State Parks do not have water hookups. They have hydrants where you can fill jugs to tote water to your fresh tank...and some have spigots where you can fill the fresh tank on your way in. If you can't reserve sites with city water, be sure your fresh tank and pump are sanitized and in good working order. Bring one or several 5 to 7 gallon potable water jugs to fill your tank from the hydrant. Be sure you have a good system for transferring water from the jugs to the fresh tank. A funnel just won't cut it.
And be sure you have a gravity fill fresh tank. The ones that require pressurized "city" water through a diverter valve are a problem to fill from a jug. You may need a transfer pump to pump water from the jug into the city water connection and then switch the diverter valve to the fresh tank. But this requires pressurized water...not just dumping from a jug. Gravity fill is much easier.
If you travel with a full fresh tank, consider reinforcing the mounts. Many won't hold up to traveling full. Other threads cover this. Pulling into Moab with an empty fresh tank might be a mistake. It depends on your final destination. Don't count on water on site unless you know for sure it's there.
It may be worthwhile to ensure that you can empty your grey tank into a bucket without contaminating it by flushing thru the black tank dump. Long stints tend to fill the grey tank quickly, and it's good to be able to dump a few gallons into a bucket and tote it to a vault toilet or bathroom to dump (don't even think about watering the trees in a CO state park). There's no point having to go to a dump station just because the grey tank is full. A three-week trip will tax many of your "systems." This is one of them.
Towing in the mountains is no joke. Whatever you have, your tow vehicle will be taxed and so will your brakes. Vehicles lose a lot of power at 12,000 feet unless they are turbos. Learn to shift manually and use lower gears on both ascents and descents. When climbing, shifting down saves wear and tear on your transmission by avoiding full-power downshifts. It's likely your TV can hold 65 mph in 2nd gear without over-revving. And using a lower gear on the 20+ mile downhills will save your bacon...and brakes. Tow/haul ain't gonna cut it out here. And, if you have a diesel, be sure you have an exhaust brake, because your diesel won't make adequate back-pressure for engine braking as you descend 5000 to 6000 feet in one continuous run. By the way, don't be surprised when some guy with a diesel dually towing a 5th wheel toy hauler blows by you like you're standing still. And the same goes for semis. There are many out here that can hold 75 MPH climbing a mountain. They ain't drivin' your father's Buick.
Finally, don't "import" firewood from "elsewhere." Pine Beetle destruction has led many campgrounds to prohibit anything other than locally sourced firewood. And be prepared for fire bans--common out here. We gave up on firewood and bought a propane fire pit
. They are actually vastly superior to a wood fire in every way. You can even run it under an awning or canopy, and you can use them in any but the most extreme fire bans.
That's my 2 cents. If you haven't been out here before, you'll love it. But it's different from "sea level" locations and camping.
P.S. If you are into a diversion for a bit of boondocking, I can point you to some spots in "South Park" (yes THAT South Park) where you can roll into the Pike National Forest and setup wherever you like...best to do mid-week. They call this "Lost Park," and the views from many sites are 360 degrees. The photo shows our spot a couple years ago in March...it was 70 degrees during the day!! Instead of I-70 as you depart Golden Gate, you'd take 70 to Evergreen, cut over to 285 in Conifer, then head southwest on 285 over Kenosha pass, then into South Park. On departure, you take 285 to 9 North through Breckenridge and back to 70.
You're gonna love it. Just be prepared.