Excellent park with the most amazing Arches. You cna get a feel for it in one day, but 2-3 days is ideal to enjoy some of the hiking rails and more remote arches.

Bring ltos of water any time you leave your car, even at sunset and sunrise. It is VERY dry. I made the mistake of taking no water on a short 30 minute hike. My keys fell out of my pocket 1/2 way through the hike, so when I got back to the car, they were gone. Ended up having to do the hike again, and was desperate for water by the end! (Only saw 1 other person the entire time I did that hike twice).

Luckily someone did find the keys and waited for me at the parking lot.

CAMPING - Devil's Garden fills up FAST in the summer so don't expect to show up and get a site. Get there early morning for a chance to snatch a site as someone is leaving if they're not fully reserved. Otherwise, not too far away is Dead Horse Point State Park - more great scenery and nice campsites too.

HIKING - I suggest heading to Double Arch early in the morning and Delicate Arch for evening. Note the trail to Delicate Arch isn't long, but is pretty steep, so allow time before the sunset. The Windows trail is a nice trail to take.

There are so many great things to do in this park. I highly recommend the fiery furnace walk guided by a park ranger. You have to buy a ticket in advance and they usually book up. You can only buy tickets for the hike up to 7 days in advance. The delicate arch hike at sunset is breathtaking (and busy). Just about any location in the park is beautiful at sunset or sunrise!

Arches, so sublime. If you are a rock/cliff person, go there. If you love to feel like you're on the set of the Flintstones, go there. If you love exploring impossible and grandiose rock formations, GO THERE. A hikers paradise, but even good for a "cruise through". But really, if you do, get out of your RV and get up close!
Tip: Plan on being there for "alpenglow", meaning sunrise/sunset light. The naturally orange rock illuminates even more vividly and slides through shades of red, yellow, gold, orange, purple, and sand. Wow.

I don't believe there is anything quite like this anywhere else in the world. This is well worth your time. A terrific movie location, used in an Indiana Jones movie for his childhood adventures. There are lots of spectacular arches -- which occasionally fall down-- so watch out. There are also dinosaur footprints and film locations used in John Wayne westerns (John Ford directing). Colorado River runs here for more fun.

With all the rock formations and natural arches, its an archeologist's dream. Gotta do the Delicate Arch hike- but be forewarned its crowded at sunset and the people up there are serious about their photography. Landscape Arch is my favorite. And Double O is a great hike too. Everyone else has said it but its very hot and dry. Don't underestimate, bring tons of water and hat/sunglasses/sunscreen.