Had a nice low level trip in the S-61N from St Mary's to Penzance Heliport in the last few weeks before the service was withdrawn in 2012. We came south around the peninsula past Porthcurno and Mousehole and I doubt we went to 1000' the whole trip, certainly on that section of the flight I'd have estimated only 500' - we appeared to be almost level with the cliff tops which I think rise to about 300' in places. Vis really was superb.