The tour of Carn an Tuirc, Cairn of Claise and Glas Maol is a popular one, and a little side trip down Y Gully would liven up the day, without taking up too much time. The gully is clearly marked on the OS 1:50000 map.
The gully gets its name due to being split at the top by a rock island. Either of the options at the start are skiable, but the skiers right is the easiest angled. As you descend, you will pass a large icefall on the left. Further round on the left is another couple of icefalls. These icefalls are becoming more popular with climbers, and it is possible that you may meet people in the gully, as it is one of the means of accessing these climbs. In relation to these icefalls, it's also important to make sure you have located the top of the right gully. Each of these icefalls mentioned are topped by easy angled snow gullies. Y Gully cuts back into the col much, and has the obvious rock island in it. Make sure you don't head off down the wrong one!
Approximate Start Height: 920m
Approximate Descent: 200m
General Aspect: North
Climbing Grade: I
Notes: Easy for Grade I
You Tube edit of Y Gully and Twisting Gully, April 2013