Sea Views/Villages close to London??

Lyme Regis, Dorset has sea cliffs and pretty views. You are correct, Port Isaac in Cornwall is too far for a day trip. You might also enjoy Hastings, easily reached by train as well as car.

Lyme Regis is lovely, as is most of the Dorset coast, but it's over 150 miles from London and will take at least 3 hours of driving to get there. I haven't heard of Doc Martin (which I assume is a play on the name 'Doc Marten', the famous 'airwear' boots beloved by generations of young Britons), but I think the problem is that you won't find anywhere quite like the Cornish coast in the south eastern corner of England near London. The coast nearest the capital is low, estuarine and muddy, not grand and rocky. The highest cliffs in the south east are at Beachy Head, near Worthing: http://goo.gl/maps/3gWUV That's only 70 miles from London, say 2 hours driving.

Perhaps you'd enjoy Dover? About 1.5 to 2 hours or so.

As had been mentioned, I think Hastings and/or Dover could be good destinations - not like Cornwall, but very pretty.

Elle, now that I know it stars Martin Clunes, I think I recall a poster at a railway station or Tube station, with him wearing a tweed jacket, but ITV isn't a channel I watch. As I said to someone else who PM'ed yesterday, for people like me who grew up in the '60s and '70s the name Doc Martin chiefly brings to mind Doc Marten's Airwear boots, which were virtually part of the uniform for many popular music subcultures here in the UK.

My wife and just returned from England yesterday (!) and had a car for a little less than a week of our two week trip. One thing I learned (and which I should have remembered from our 2000 trip) is that unless you are on the "M" motorways, expect it to take longer than you expect it to take to get anywhere. Take what you see on Google maps in terms of travel time and multiply by 1.5. So, you should probably stick to the southeast in terms of day trip driving distance from London. Dover does have dramatic coastline but may not be anything like the TV show you mention. I would go out of my way to avoid driving anywhere close to central London, but it sounds as if you are quite a bit more adventurous than I am. Oddly for a country with so much coastline, relatively little of the best of England seems to be on the coast. Not sure why that is. It's much in contrast to Ireland where the best parts tend to be on the coast. The Cornwall coast is said to be the exception, also Jurassic Coast looked intriguing to me in our recent planning, though we did not make it there. Maybe it's just that the interior parts are so great that the coast does not get its due.

Take a train down to Brighton. Look around Brighton and the beach. Tour the Palace. Rent a car and drive east through Seahaven and Seaford to Beachy Head. Get out for a look at the cliffs and either continue on to Eastbourne and back, or directly back the way you came. If you prefer a castle with your beach, train to Dover, tour Dover Castle.

Thank you so much everyone for your fantastic suggestions! Lots to research now! I appreciate the insight and help. Cheers!
Anita