The document discusses how changes in locational factors have impacted the distribution of the British iron and steel industry over three phases from the 18th to 20th centuries. As resources depleted, the industry relocated based on new locational advantages - first to coalfields in the 19th century for fuel, then coastal areas in the 20th century for imported materials and transport access. These shifts led to economic decline in some inland areas but also opportunities for new industries and unemployment relief in affected regions.