Painted Rocks at Alpine Lake.
The Painted Rock is a viral trend where people, commonly children, paint pebbles or cobbles and leave them for others to find and collect.
What to do when you find a painted rock?
You can either take this rock home or hide it where you found it, or move to another location for others. In general if you find a rock out by itself you CAN keep it, but usually the hope is that you will either re-hide it or enjoy it at home for a little while then re-hide for someone else
Alpine Lake Rocks have a FB site where you can post a photo