Tunnels underneath the River Thames constructed up to 1999 for the Millennium Dome; and a tunnel to the site of the old Ferranti power station on the east side of the mouth of Deptford Creek. There is also a tunnel between Cottons centre and the old Billingsgate Fish Market near to London Bridge. Citibank used it for cabling at one point; it was large enough for a person to walk through. The Silvertown Tunnel is a new Thames river crossing proposed to supplement the existing Blackwall Tunnel, which will join the Greenwich Peninsula with West Silvertown. There is also a further tunnel about two miles
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