Floated the Middle CO between Pinball and Lyons Gulch on Friday. A new thin wire cable has been strung river right from the right bank onto an island and back onto the bank river right. It is about 1 mile below Horse Creek, between river miles 57 & 58 on the BLM "Upper CO River Rec Area" map up_colo_riv.pdf. It is just downstream where the river begins an S shaped bend to the NW away from the road and RR tracks on river left. There is a new cabin/gazebo being built on river Rt. The cable has no flags or other warnings, and we were unaware of it until we had floated alongside it for a few hundred feet. The good news is the main channel is clearly on river left, but it is strung at a dangerous level for unwary rafters.