[irrational]

I see some dotted lines nearby on the Google map. Hiking trails? Jeep trails? I’m wondering how much that thing weighs and how they got it there. Maybe drive it there with a large off-road pickup truck and then got a bunch of guys to carry it down the wash behind it?

[toufka]

It's pretty near Moab, UT - which is an adult kid's playground. The area is abundant with trails. Much of that land is regularly explored with various 4x4s for sport, even (and especially) off the trails. And Moab would also be a place enriched for people with the skill and desire to make a giant metal slab and find a place to stash it.

The 'monolith' is just a bit SE of the "Dead Horse Point" (SW of Moab), just on the east side of the river on this map [1].

[1] https://www.discovermoab.com/4-wheeling/

[subsubzero]

I see a small dirt road immediately to the north. Given that dirt road intersects with hwy 211 I assume it was driven there in a large ATV. Most likely a 4wd truck and a large ATV went out there with the sculpture in the truck, and then the ATV and a few people with shovels drove it down to the gully to the site to install it.