19th-century London a network of smaller tunnels away from the River Thames and out of Central London, towards the Northern Outfall Sewer at Beckton in East London. The Victoria Embankment also allowed an extension of the Metropolitan District Line underground to be built, from Westminster east to Blackfriars. In total, the Victoria Embankment reclaimed over 37 acres of land from the Thames, allowing a broad east-west boulevard to be built and a series of public gardens. All three sections of the Thames Embankment are faced in grey granite, mounted with handsome cast iron lamps, and lined with London plane trees. In 1878,
Tunnels underneath the River Thames the Port of London, which until the 1980s required large ships to be able to access the river as far upstream as the City of London. Until the construction of the Queen Elizabeth II Bridge in 1991, the easternmost bridge on the Thames was Tower Bridge in central London. Even now, the Dartford Crossing provides the only way to cross the Thames by road between London and the sea (with predictable results for traffic congestion). The width of the river downstream meant that tunnels were the only options for crossings before improvements in technology allowed the construction of high bridges