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Outer Left Twin Crack  Queen's Entrance to Ariel Cave (Blacknor Hole)  Persil Rift  Hopeless Hole  Gemini Rift  Steve's Endeavour Rift  Bullseye Fissure  Saint George's Rift  Anniversary Rift  Showerbath Cave  Sharbutt's Rift 2  Sharbutt's Rift  Sandy Hole (Portland)  Clay Ope Dig 

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Ariel Cave (Blacknor Hole)

Westcliff, Portland.

NGR:SY 67908 71665
WGS84:50.54386, -2.45427
Length:875 m
Depth:0 m
Altitude:0 m

Portland's premier cave for geological and sporting interest. Vadose passages below tabular-chert roof, heavily invaded by much younger mass-movement rifts. Some coloured formations. Access (2020) from abseil take-off alongside coast path on top of cliff or by climbing bolted sport route (Drag Racing Underground) from below. Ensure you are not breaking any seasonal bird-protection restrictions before using the main entrance. A second entrance (Queen's Entrance) exists 45 m south at the same altitude however there is no easy access from either above or below.

Connected to Sandy Hole via a very difficult and tight rift providing a long and sporting through trip. Combined length of caves is ‭2,489‬ m.

More commonly known as Blacknor Hole.

Alternate Names: Blacknor Hole

Notes: Karst / Mass-movement hybrid system

Hydrographic Feeds: Long-lost to erosion of catchment. Some evidence of river valleys to E & W of Portland.

Ariel Tunnel & Blacknor Fort System, M. Read, 1990
Blacknor Hole (page 1), M. Read, Weymouth & Portland Venture Scout Unit , 1988
Blacknor Hole (page 2), M. Read, Weymouth & Portland Venture Scout Unit , 1988
Blacknor Hole (Piccadilly Circus), M. Read, Weymouth & Portland Venture Scout Unit , 1988
Blacknor Hole, Hardye's School CCF, 1975
Blacknor Hole, McTavish, 1975

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This entry was last updated: 2023-03-29 18:59:17

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