ALG-363, Black Hole Arch, North Idou Area Outskirts. 3 meter span (estimated). This arch is located below ALG-362 (Head Dress Arch) and this is the first opening seen during approach. The arch is so close to the adjacent rock that you can only photograph a "black hole" (hence the nickname). The needles visible in the background of the photo shelter ALG-380, ALG-381, and ALG-382.