We noticed several piles of rock along the trail. They didn't appear to be part of a wall or anything else that we could think of.

Creation Date: 2016-07-04 09:17:15
Modification Date: 2016-07-04 09:17:15
Camera: NIKON CORPORATION / NIKON D5100
Lens: Nikon AF-S DX VR Zoom-Nikkor 18-55mm f/3.5-5.6G
Aperture: f/5.3
Focal Length: 40 mm
Exposure Time: 0.016666666666667
ISO: 3200
MeteringMode: 5