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In Medieval times, there... forts along the river to defend
London. There... one bridge called London Bridge and there
a lot of traffic on it as it... the only bridge to cross the River
Thames. There ... wooden houses and the streets... very
narrow, so fire... a constant risk. There... a lot of shops
and there... a big market for cattle in Smithfield. Sir Henry
Fitz-Ailwin... the first mayor of London.