Design a cave symbol of OS maps

[bagpuss]

My daughter mentioned this competition and thought it might be of interest:
http://www.bbc.co.uk/programmes/articles/3hzTn09hQZykyDCn9l4M5yB/the-one-show-ordnance-survey-limited-on-the-map-design-competition

One of the symbols there are looking for is for 'caves', although there's no guarantee OS will actually use the winning entry (see terms and conditions) it would be good if a caver won it

 

[cap n chris]

Omega is a common symbol for caves, apparently.

 

[Blakethwaite]

?  :

 

[alastairgott]

The maps in montenegro use a semi circle with a dot underneath it.

See key on this map:
http://www.durmitor-autocamp.com/files/Durmitor-Mapa.jpg

 

[cap n chris]

"I'm sorry Dave, I cannot allow you to do that", springs to mind. Without the dot it would be more cavey, reckon. 

Perhaps the symbol should just be a smiley-face. 

 

[Nigelh]

Surely in our risk averse society it should be a 'skull & crossbones'. 

 

[Alex]

Perhaps they don't bother with a symbol and just use a hole punch?

 

[martinr]

 

[martinr]

 

[Pegasus]

Perhaps they don't bother with a symbol and just use a hole punch?

Brilliant