Chimney Climbing under Rock Climbing
Method :
Back-and-Foot - Pressing the back against one side and feet against the opposite rock-wall.
Stemming - Using wide-spread legs to press against both rock-face-wall simultaneously.
Bridging - Utilizing hands and feet on opposite sides to span the gap.

Safety
Primary Risk - Falling > Fall prevention - Belay system (Ropes)
Key Safety Tool - Wide-range Cam

I learned this technique at SuSunia Hill (Bankura) during BASIC 'Rock Climbing Course" under supervision of "The Institute of Exploration" Calcutta, with my BASIC IoE Team/Rope-I member's.
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