Mammoth
Cave
cave entrance with sandstone cap
Mammoth Cave entranceMammoth
Cave
cave entrance with sandstone cap
Mammoth Cave entrance
"breakdown" in cave room
tour route
large
room
scenic tour
column & stalagmite
stalactites
& stalagmites joined
magnesite balloon 
calcite
crystals in crack
dogtooth spar
nailhead
spar
draperies
flowstone
calcite "bush"
soda straws
water
drop
boxwork
helictites
frostwork
popcorn
and helictites