I've hiked Blue Ridge, and I've hiked the East Fork, but I ain't never seen Prairie fork. Today was the day!
The drive down the dirt road was just fine in my Subaru. My only trouble was going slow enough to dodge the occasional big rock in the road - the ones that suddenly appear around a corner, just waiting for you to be not paying attention. At Lupine, there were several SUVs and tents. It was nice and quiet, and I felt bad disturbing the peace of the morning by driving in. (it was about 10am).
My big plan (oh, I always have a plan) was to ride my bike as far toward Cabin Flat as I was able, then walk from there, hopefully to the junction with East Fork. Within 5 minutes, and right after talking to a nice man and his young son who looked at me like I was insane to be on a bike, my back tire went completely flat. No rescue, flopping around flat. So I ditched it in some bushes and just went for a hike.
The photo doesn't capture this, but most of the road (about two miles of it) is paved with dark purple lupines that smell like grape Bubble-icious gum. There were several drunken bees along the way as well.

Washouts show why this is no longer an option for vehicles:

Baden-Powell looms in the distance, while the road continues far right:

Bighorn!

Cabin Flat picnic tables being reclaimed:

Disappointingly, this is the condition of the route west from CF:

The creek flows with Sapphire Gin:

So I did not go any further today, given the brush. However, this sign welcomed me to try again someday:

Looking upstream back toward Lupine:

What a super nice place to get away from it all!
Has anyone traveled those mysterious last two miles in recent history?
Stats - about 5 miles total, 3.5 hours which includes mucking around with the bike, and looking at tracks. Saw Bighorn adult and lamb, adult bear, and lots of fox/coyote tracks all along the way. Nice butterflies too!