Trinity Canyon — One of the smaller drainages on the north side, Trinity is larger than most canyons on the south side, and more complex. Very hard structures of Vishnu in this area make Trinity narrow, winding, and impassable. Trinity is a well-known pothole water source (west fork granite tanks) and may have a good flow of water here in the winter or spring, but it can be dry and is not considered a reliable water source, and there is no river access from the upper bed. Unless there is good seasonal flow or recent substantial rains, the water quality will be soft-salty and not suitable

Routes — Part of the Crystal/Phantom Loop in GCLH-I. The quickest access from Bright Angel is by Utah Flats (no kidding) to Cheops/Isis saddle, and along the southern flank of Isis Temple. There are a couple of other ways that would seem shorter, but not. The eastside access into the east fork is a break formed by a fault alignment across this drainage directly west of the divide to Ninetyone-Mile, and entry to the main bed crosses the nose at the join.

Two large Tapeats blocks near streamside provide nearly perpetual shade with no unpleasant surface heating in the warmer season. Various places show signs of lion activity here, with a number of attractive overhang shelters in the upper Tapeats, and we are sure there was one not seen but moving in the brush of the east access ravine.

The west access is under a small hill on the Tapeats slope not far from the shady spot. This access shows signs of modern improvement associated with the tram engineering crew that once worked the westside point of Trinity, and at a corresponding location on the other side below Dana Butte there are timbers at the edge of the rim.

To locate the recently cairned access out of Trinity, go upstream to the next drainage bay which is cliffed in the headwall. Start up from this unattractive drainage access, and then proceed north upslope to the base of the unconformity exposure. Go left and look for trailbed improvements and cairns leading to the point above the Tapeats cliff. A hint of travel sign turns south just at the edge of the Tapeats rim. The base-camp for this expedition was near the rim just before Trinity opens on the river. Upslope from the minor Tonto saddle near the point a cleared platform makes an appealing leave-no-trace and cactus-and-mosquito-free camp, most likely also from the tram crew

Continuing up Trinity and following the upper east fork will lead to a walkup through the Redwall above Phantom Creek, and then on to Shiva saddle and the rim. A collared lion took this cross-canyon connection down Hermit Trail, swim to 94-Mile, up the fault ravine, to Trinity and then to the North Kaibab forest -- expert navigation.

Downriver to Ninetyfour-Mile Canyon. The nearby accesses are to upper Phantom Creek going over the Cheops/Isis saddle, or over the divide into the basin above Ninetyone-Mile Canyon; both of these locations are access to water from here if that is a problem.

1996 December - First exploration with Danny, coming from 91-Mile Canyon, going out to the point upriver (Steck’s "emergency water route" looks scary). We then followed the Quartzite terrace along the base of Isis into Phantom Creek (good, fast track). Many antlers on the mesa; 6 deer spotted. Cave with lion mound along descent ravine into east fork (easy travel).

2004 November - From Shinumo, a late lunch stop with ample water supply in the granite upstream on the west fork. Then on to Camp 8 at the divide above Ninetyone-Mile. Next day, continuing across the Cheops/Isis saddle heading for Utah Flats.

2015 April - Two stops here, outbound to 94-Mile and returning from same. Even after a good rain the water is not friendly but we did find it drinkable with no bad consequences from the larger pools below the fork.