I have been working on doing the Mainland/Sweet Surprise circuit at Ginnie. I have been down Mainland to the T's that start at about 3,800 feet with no problem.

The other day I went down Sweet Surprise and jumped to Mainland at 2,900'. This tunnel is low and silty at the beginning. I went a 100' or so and hit a narrow vertical restriction that I realized I would have to turn sideways to get through in sidemount. As I was sizing up the restriction, my silt caught up with me and was in a complete silt out. Since I couldn't see the restriction or my guages, I decided to turn back.

This seems to be a tunnel that you want to go through and complete the circuit and not come out the way you came.

The tunnel from the jump at Sweet Surprise to the 1st T in Mainland seems to be about 800' based on the map.

Does this tunnel open up at all after the 1st 100' feet or is tight and silty the whole distance??