Dahej is one of India's largest chemical and petrochemical hubs. Along the Gulf of Khambhat, the Dahej PCPIR (Petroleum, Chemicals and Petrochemicals Investment Region), the GIDC estates and the port bring together reactor blocks, tank farms, pipe racks, jetties and utility plants spread over many acres. From the ground, it is almost impossible to show the scale of these sites. From the air, it takes a few seconds.