This card comes from an Italian ex-pat living in London. She's very active and is training to run a 10 k.  This beautiful card shows one of London's iconic symbols, Tower Bridge. Tower Bridge was constructed between 1886-1894 and spans the River Thames. It is 290 metres long and 65 metres high. The bridge was officially opened by the Prince and Princess of Wales (the future Edward VII and his wife, Alexandra of Denmark). Because the Thames is a busy commercial river, the bridge had to allow large ships to pass beneath it. The raising mechanism when the bridge first opened was powered by pressurized water stored in six hydraulic accumulators, with two pairs of engines on each pier. The original operating system was largely replaced in 1974 by new electro-hydraulic drive system. Oil is used in place of water as the new hydraulic fluid.  During the first year of Tower Bridge, the bridge was raised 6160 times, or about 17 times a day. River traffic is much reduced these days and t...