In between Fort Greymoor and Rorikstead I found a circle of three puzzle towers - those ones with whales, snkaes, and eagles in them that you turn, a pillar with a handle on it that can be maniplutaed, and an entrance into the ground with a gate over it.

I have looked on the different Skyrim maps available, and all I can think it is is one of the shrines of Zenithar - but it seems a little complicated for that.

Does anyone know what this place is, how do I get in, and what can I expect when I get inside?

Here it is:

http://www.uesp.net/maps/srmap/srmap.shtml?locx=-31760&locy=-23968&zoom=17

It's called The Puzzling Pillar Ruins. You have to rotate the pillars to get the trapdoor to open gaining access to a chest!

Thanks!

When I first encountered this, I couldn't figure it out. Later, I found the "hints" lying around. I felt dumb lol

I found them. I had no idea what the hell they were. Rarely found them, at all.
So they lead somewere I take it.
Though finding them again could be hard.

They lead to a chest with a skeleton. Some leveled minor loot.

You can easily find it again by walking in a straight line from Sleeping Tree Camp to North Brittleshin Pass.

Yes, they are easy enough to find. And you can use the map link that I posted.