High and Low Tide are measured over a 15 year average from Sea Level at Newlyn Cornwall (tbc). Mountains have triangulation obelisks but height is now measured by satelite and can vary minutely according to weather depressions or cyclones. The Ordnance Survey was for military purposes. England has very good accurate updated maps. Tidal range varies greatly and penetrates far inland. A single tidal wave called The Servern Bore is a known phenomenon. Chalk cliffs are most often far higher than the tides and vertical.
The English Weather varies much even diurnally and the English like to talk about the weather outdoors. Foreigners may practice English phrases about the weather on passing English walkers and cyclists depending on speed and opportunity. Choose well dressed older locals for questions: They will enjoy the chat. Much knowledge of climate is intuative and often detailed. Keep the conversation short. Stop for a short while. If the English point vigourously if you ask for directions, that means they are local and want you to go. but this is polite not serious or rude.
Weather sweeps in from all compass directions even on the same day. Because the south coast lies latidutinally this can mean cycling with or against the wind. Why not cycle with the wind on a hot sunny day? Some old naval concrete derelict shores from the D-Day preparations are are great to be windswept across as at Newhaven. Wear light technical and stylish clothes for light rain showers.
In English resorts buy seafood in selected places like Whitby, Leigh-on-sea and Whitstable. The Thames Estuary is great for fresh, safe and healthy seafood. But eat fish and chips in every resort with peas and vinigar and salt either indoors or outside. Indoors also buy bread and butter to make chip sandwiches. Order tea.
The best fish and chips are the main bigger shops on the corners by the pier with bright tiled interiors and stylish parlours. Avoid smaller vendors which offer kebabs or other fast foods. You can refuse plastic packaging, it is not impolite.
Dispose of food wrappings near the shops carefully.
Lots of old people retire to or visit the seaside. Young people and families holiday there too. Spend a little time after fish and chips just watching the English on holiday.
Travel now to Swanage, Dorset by (Waterloo) Wareham a (formerly) walled town in Hampshire.
Stay on the coast. Do not try to get back to big inland cities by train with a bicycle from a crowded seaside resort.