Palmer Creek Road, South Dakota

[HandsomeRob]

Palmer Creek Road is a gravel road about 3 miles long between the Needles Highway and SD-244 in Pennington County, South Dakota. I drove on it the other day and found one of the most curious features I've ever seen on a minor gravel road.

Traveling northbound, a sign indicates the road will divide. After the divide, you pass under a bridge carrying the southbound lane, then merge with the same southbound lane and pass through a gap in a rock outcrop. Then there is a split, and you have to take the left hand fork to continue northbound. After a few turns you rejoin the southbound lane and the road reverts to a typical gravel road.

I can't for the life of me imagine why such a minor road would be designed in this way. There must be a story behind it, but the explanation eludes me.

[NE2]

Perhaps they wanted to make sure everyone going either direction passes through the rock formation without making it two lanes.
http://www.untraveledroad.com/View?/USA/SouthDakota/Pennington/BlackHills?w=51B

http://www.northernplainshighways.org/sdakota/sd200up.html

It replaced an earlier (still gravel) road designed and built by Norbeck, then called the Horse Thief Lake Road. The remaining west end of that road, featuring an unusual divided highway with figure-8 at-grade and separated-grade crossings, is now called the Palmer Gulch Road and still appears (unlabeled) on SD DOT highway maps.

Seems it was once one of the main access roads to Dead Guys in a Cliff.

Incidentally, US 16A loops over itself at least thrice in the area.

[rte66man]

Incidentally, US 16A loops over itself at least thrice in the area.

And on wooden trestles no less.  A deliberate design function (the loops that is). I have the quote in a book on Rushmore that I will have to get posted later.

rte66man