ALG-369, Huge Boulder Arch, North Idou Maze Area. 33.5 meter span (measured), 9 meter height (estimated). GPS 32R 550721 2751680. From ALG-368 (unnamed arch 89) continue north 300 meters and walk up the sand slope to the arch on the left. This arch of over 100 feet is a great challenge to photograph. A huge boulder sitting under the arch blocks a major part of the span from view. This arch is also the key to a fabulous labyrinth of natural arches. Welcome! It is a-maze-ing!