Since the late 1980s, Hall has created a significant body of work for the open air that evokes a sense of calm, order and contemplation. His abstract sculptures are grounded to the floor by the density of his chosen material, and define space using light, shadow, scale, and three-dimensional mark-making. Placement in very important to Hall, who has spoken of setting up a choreography between a piece and its location, and his sculptures are inspired by his experience of walking in the landscape.

The 10-metre-wide Crossing (Horizontal) is made of Corten steel and invites the viewer to consider the work from many angles and distances, or in different seasons, and changes shape depending on how the work is approached. Horizontal, vertical or diagonal lines are commonly seen in his sculptures, and interact with their natural and urban contexts. A sister piece, Crossing (Vertical), is on display in the town centre in Barnsley.