The signature photo of Island in the Sky is the view through Mesa Arch.
The Island in the Sky section of Canyonlands National Park could not be better named.
It’s a high Mesa at the junction of the Colorado and Green rivers.
Most of the longer hikes drop precipitously off the “island”. There are several to choose from: Gooseberry, Wilhite, Alcove Spring. Many hikers climb down quickly and are picked up by an off-road vehicle on the White Rim Road. If you do not have vehicle support (and it’s not too hot), you can switchback your way up top again, sometimes via a loop.
The Rangers when I was there recommended Murphy Basin, a 10mi (16km) lollypop loop with an optional sidetrip to Murphy Point. Non-stop fantastic vistas.
my view from Murphy Point
The best hike on Island in the Sky for me, however, is the Syncline Loop.
besthike.com 
How can you get lost? It is an island!!!
Great question!
Anyone in their right mind could walk towards a landmark, or the sun, and reach the edge. Then walk along the cliff until they found the road.
The man who died near Grandview Point was found in a sandy ravine; “he became panicky and retraced his way not once but twice, and where he had struggled up an alluvial bank to the ledge. From that point he could see the juniper with its promise of shade. Somehow he made his way to it, laid himself down and never got up again.”
(Edward Abbey)
Perhaps not “lost”, but disoriented. Then dehydrated and weak.
Having just been there, it is easy to get confused when following stone cairns. You backtrack a lot.