This category is within the scope of WikiProject Geology, an attempt at creating a standardized, informative, comprehensive and easy-to-use geology resource. If you would like to participate, you can choose to edit this article, or visit the project page for more information.GeologyWikipedia:WikiProject GeologyTemplate:WikiProject GeologyGeology
This category is within the scope of WikiProject Geography, a collaborative effort to improve the coverage of geography on Wikipedia. If you would like to participate, please visit the project page, where you can join the discussion and see a list of open tasks.GeographyWikipedia:WikiProject GeographyTemplate:WikiProject Geographygeography
This category is within the scope of WikiProject Years, a collaborative effort to improve the coverage of Years on Wikipedia. If you would like to participate, please visit the project page, where you can join the discussion and see a list of open tasks.YearsWikipedia:WikiProject YearsTemplate:WikiProject YearsYears
This category is within the scope of WikiProject Caves, a collaborative effort to improve the coverage of caving and cave articles on Wikipedia. If you would like to participate, please visit the project page, where you can join the discussion and see a list of open tasks.CavesWikipedia:WikiProject CavesTemplate:WikiProject CavesCaves
Start a discussion about improving the Category:21st-century sinkholes page
