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,
River Thames Thames Estuary), the river is subject to tidal activity from the North Sea. Before the lock was installed, the river was tidal as far as Staines, about upstream. London, capital of Roman Britain, was established on two hills, now known as Cornhill and Ludgate Hill. These provided a firm base for a trading centre at the lowest possible point on the Thames. A river crossing was built at the site of London Bridge. London Bridge is now used as the basis for published tide tables giving the times of high tide. High tide reaches Putney about 30 minutes later than