Where would an invader find Britain's best landing ground?

What are the best areas for a naval landing in Great Britain?

The south coast, especially Sussex and to an extent Kent, offers suitable beaches and flatter ground for movement inland.

The south coast offers beaches with gradients suited to landing and flatter ground for moving inland. Sussex is the preferred example, with Kent qualified as suitable to an extent. Norfolk shows the limitation of judging a coast by its beaches alone: an army could land but then face difficult inland ground. Cornwall's moors pose another obstacle after troops leave the coast.