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The Royal Military Canal stretches for 28 miles hugging the old cliff line that borders the Romney Marsh from Hythe in the north east to Cliff End in the south west. It was built as a third line of defence against Napoleon, after the British Royal Navy patrolling the English Channel and the line of 74 Martello Towers built along the south coast. The Royal Military Canal was constructed in two sections. The longest section starts at Hythe in Kent and ends at Iden Lock in East Sussex. The second smaller section runs from the foot of Winchelsea Hill to Cliff End. Both sections are linked by the Rivers Rother and Brede.

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In the United Kingdom, a scheduled monument is a 'nationally important' archaeological site or historic building, given protection against unauthorised change.
There are about 20,000 scheduled monuments in England representing about 37,000 heritage assets. Of the tens of thousands of scheduled monuments in the UK, most are inconspicuous archaeological sites, but some are large ruins.
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