Hole in the Wall 10 more beyond Big Ben

1/5/2023 Hole in the Wall Cave Near Marianna FL. Merritt's Millpond. We dove upstream to Century Tunnel Past Big Ben and London Bridge toward the Champagne Bottle but did not quite get there. We used DPVs most of the way then Swam. My buddies were on back mounted electronic CCR units with a pair of AL 80's and an AL 40 for bailout. I used open circuit sidemount with E8130's for main tanks and 3 AL 80's for stages. The DPV and swim speed was well below average and the vertical fissure cracks etc beyond London Bridge were something for my buddies to get through in their configuration. We had 4 DPV total as I was towing a spare. Cave Diving, DPV, side-mount, open circuit, eCCR.