Gustavo Almeida Couto de Andrade:
Speleothem's watcher
Gustavo Almeida Couto de Andrade:
The real dark and deep cave
Gustavo Almeida Couto de Andrade:
Point in the big hole
Gustavo Almeida Couto de Andrade:
Getting dark
Gustavo Almeida Couto de Andrade:
Penetration in darkness
Gustavo Almeida Couto de Andrade:
Watching gallery