The transition from sail to steam shipping shaped the later-nineteenth-century Port of London. When limited to river trade and traffic, steamers had little effect on facilities. Once improvements in technology extended the economic viability of steamers on ever more distant passages, larger and deeper docks were needed. This led to existing facility improvements and downstream docks. The new steam port, served by major shipping lines, depended on barge transhipment of cargoes to waterfront wharves, which flourished as a result. Trade volumes responded to metropolitan population growth, but the national share remained stable or fell. Wool and grain replaced sugar as leading trades. Re-export business declined. The capital’s relationship with the port changed. In the 1860s, its perceived importance led to the rejection of an eastern Thames embankment. In the 1880s, Tower Bridge went ahead.