Luweng is Cave in indonesian , so its mean "Grubug" Cave,
"luweng grubug" is part of "kali suci' underground river system in gunung sewu karst,Jogjakarta-Indonesia, Grubug cave is 120 metre vertically, you can find the river in the bottom of this cave,so it is make the picture too foggy....
descending the "luweng grubug"
from outside
greeting from indonesia
ridho
ridhoGB@gmail.com