M. David Nelson:
Great Sand Dunes NP
M. David Nelson:
Great Sand Dunes NP
M. David Nelson:
The Challenge from within
M. David Nelson:
Sun and Sand
M. David Nelson:
Spider Rock
M. David Nelson:
Canyon Stream
M. David Nelson:
Bryce Canyon NP
M. David Nelson:
Pecos National Historic Site
M. David Nelson:
On the Canyon Rim (Explored)
M. David Nelson:
White House Ruin
M. David Nelson:
Canyon de Chelly 2
M. David Nelson:
Ruins
M. David Nelson:
Canyon de Chelly (Explored)
M. David Nelson:
A Tree in the Desert
M. David Nelson:
Spider Rock