§ THE
LAST MAJOR
UNDAMMED RIVER IN THE ARID SOUTHWEST.
§
RUNS THROUGH TWO
MAJOR ECOREGIONS.
§ TRANSITIONS BETWEEN FOUR
MAJOR GEOGRAPHIC PROVINCES:
n EAST - CHIHUAHUAN
DESERT
n WEST - SONORAN
DESERT
n NORTH - ROCKY
MOUNTAINS
n SOUTH - SIERRA
MADRES
WHY IS THE SAN PEDRO
A LAST GREAT PLACE?
