- The Virtual Cave
- A wide-ranging introduction to the geology of caves. Organised by geological feature with pictures and clickable virtual maps. - Bill Storage - Speleology - Photographs and articles dealing with speleology and cave exploration.
- California Underground Online Exhibits - An overview of the formation of caves, cave conservation, photography and wildlife together with local educational resources. Diagrams, pictures and slide shows.
- Cavechat.org - NSS discussion forum for US cavers including sections for cave diving, news, conservation, equipment, photography, rescue and surveying.
- Caving From Spadout - Articles on the terminology, techniques and gear used for caving. Discussion boards, editable information, feedback and links.
- U.S. Cavers Forum - Discussion forums including caving, the NSS, the study of speleology, cave conservation and management, bats and gear.
- UIS International Speleo Calendar - Events around the world.
- World Cave Database - A list of long and deep caves from all around the world. Listed by depth, length and country.
- Biospeleology@ (14)
- Cave Diving (41)
- Cave Photography (20)
- Cave Rescue@ (29)
- Cave Surveying (17)
- Directories (16)
- Equipment Manufacturers@ (14)
- Organizations (362)
- Personal Pages (49)
- Publications (11)
- Shopping@ (37)
- Show Caves (144)
- Tours and Training (11)
- Urban Exploration (623)
- Weil's Disease@ (12)
