The higher land on either side of the valley – the Western Heights and the eastern high point on which Dover Castle stands – has been adapted to perform the function of protection against invaders. The town has gradually extended up the river valley, encompassing several villages in doing so. Little growth is possible along the coast, since the cliffs are on the sea's edge. The railway, being tunnelled and embanked, skirts the foot of the cliffs.
The higher land on either side of the valley – the Western Heights and the eastern high point on which Dover Castle stands – has been adapted to ,perform the function of protection against invaders. The town has gradually extended up the river valley, encompassing several villages in doing so. Little .growth is possible along the coast, since the cliffs ar,e on the sea's edge. The railway being tunnelled and embanked skirts the foot of the cliffs