Part - The Secret Island
Chapter - Backside
Report going from Egg Room to Backside: say "You push through vegetation blocking a gully leading out of one eroded side of the crater[if a random chance of 1 in 2 succeeds][time-of-day-bit][end if]. The ground quickly drops off and descends at a sharp angle towards the sound of the surf, not far below.". Report going from Backside to Seal Beach: say "You scramble down the last of the canyon to firmer footing on a rocky ledge.". Report going from Backside to Egg Room: say "You clamber up the last steep slope of the gully and climb back into the crater.".
The prose name of Backside is "the steep canyon behind the egg ship". The description of Backside is "[backsidedesc].". To say backsidedesc: say "Descending at a rate that requires both hands and feet to navigate, this debris-choked stream bed, dry at the moment, tumbles down the cliffs that make up this side of the island. Below, waves beat heavily against the cliff. [paragraph break][exits]". The exits text of Backside is "The gully continues [down] or [up]". The printed name of Backside is "Narrow Gully".
Backside-stuff is stuff in Backside. Understand "gully/side/crater/angle/bed/stream/cliffs/cliff" as Backside-stuff when location is Backside.
Instead of sleeping in Backside, say "It's too steep here for that.[sleepsuggest]".