Diminishing dimensions downstream...?

[Rob]

The first is Peak Cavern as Pitlamp says...

And it should be noted (preferably by the original poster) that the photographer was Brendan Marris.

 

[graham]

And it should be noted (preferably by the original poster) that the photographer was Brendan Marris.

Is it? Sorry, I simply found it by a Google image search and the Flickr page does not give the photographer's real name.