Draught horses were at the very heart of the metropolitan economy, underpinning the livelihoods of thousands of people. Industry and global trade generated an astonishing amount of haulage work for horses, yet while the expansion of waggon services has been studied, the vital intra-urban haulage work performed by cart and dray horses has been overlooked. Carts were used to carry a panoply of goods and waste between wharves, warehouses, markets, shops, houses, pits and construction sites in Georgian London. A wide range of tradesmen and shopkeepers came to depend on draught horses and benefited from major improvements in their breeding in this period. The Midland Black type of heavy horse became one of the most powerful symbols of industrial progress in the city, playing a central role in the expansion of London’s coal and brewing trades, spurred on by the adoption of steam power. These animals were bred to withstand London’s unique work environment but the intensification of demands thrust on their bodies also necessitated improvements in their diet, stabling and care.