what are those rock piles?

yes it makes more sense that the ones ive seen in pt magu and mscp are trail markers to guide people.
the one in pt magu is at an unmarked intersection along the guadalasca single track. a bit north of the overlook/hellhill/guadalasca junction there is a fork that is unmarked and you gotta go right to hit the guadalasca single track. its at this unmarked fork that i saw these rocks. i gotta pay more attention next time i go there to see if it is a true "duck" with a pointy rock showing the right path to the singletrack as shown by the link kindly provided by sc_nomad.
thanks to all that contributed to this thread

 

I took the attached pictures at Namtso holy lake in Tibet. Rock stacking there is a ritual the pilgrims do during their walk around the lake. I imagine the rock stacks (that aren't trail markers) here in the States have a similar purpose in the patience, balance, and meditation involved in creating a good one.

 

In Hawaii and some other places, people build these rock cairns as a memorial to deceased loved ones.

For some, building them is a kind of prayer or meditation. It's hard to think of other things when you're balancing rocks. It takes body, mind and soul. Very Zen.

Given the diversity of replies, I guess we can say tht a lot of people, for a lot of reasons, take the time to gather rocks and build a cairn and say "here... now".

 

Kind of hard to build snow people in this climate.:?:

 

If u r going to stack them at least stack them into the shape of a ramp!!

 

:lol:

 

looks like a rock penis

 

hah, those are all over my local trails