One of the sunniest, gentlest days of midwinter, and 18 OUGS members, spanning an age range of some 70 years, met at Sidmouth Museum in the centre of this Regency town on the South Devon coast. The museum occupies one of the oldest buildings in town, the former Customs House. Its Honorary Curator is Dr Bob Symes, who has retired from the Natural History Museum in London to run this delightful little building, with its eclectic displays of Sidmouth's history. Emphasis is placed on the geology of the area, it being on the western end of the World Heritage Site (WHS) known as The Jurassic Coast, opened by HRH Prince Charles as recently as October 2002.

Dee Edwards introduced Dr Symes, who, having modestly described himself as just a mineralogist, explained the message he wants the museum to convey. The WHS is an almost complete sequence of the Mesozoic, representing 185 million years of earth history in just 95 miles. Starting in the west, at Exmouth, the Triassic sequences exposed on the coast become younger as we head east, until at Lyme Regis we meet the Jurassic rocks which predominate along the Dorset coast. Then we meet the Cretaceous, which forms Old Harry Rocks at the eastern end of the WHS. Bob used the visual displays in the museum to describe the Sidmouth area through millions of years, from when it was part of Pangea, via the arid desert belt, the Variscan orogeny, to 240 Ma ago, when erosion from the Cornubian mountains led to sedimentation in what is now East Devon. He asked us to imagine a huge Nile-like river flowing here from Spain, through the deserts of France, its deposits forming what we know as the Budleigh Salterton pebble beds.

With vivid imagery, Bob outlined the geological processes which led to the famous Hooken landslip of 1790, the Wych Farm oilfield (largest on the British Isles), the local cosmetics industry (ground up pebbles) and the presence of radioactivity, requiring radon monitoring in Sidmouth, despite its distance from outcropping granite. He briefed us on the nature of the scenery we would shortly be viewing in the outdoors and then invited us to tour the museum. There was plenty to see, by no means all of it related to geology - like the Honiton lace exhibition - and it was interesting to see how local personalities have contributed to the understanding of Sidmouth's natural history. One of Bob's heroes is the historian and diarist Peter Orlando Hutchinson, whose activities covered much of the nineteenth century and whose sketches accurately depict the cliffs and coastline before erosion produced what we see today.

Leaving the museum, we spent a couple of hours exploring the coast immediately to the west of the town. I was astonished by how much one could see, even at very close quarters, without straying from the Esplanade and the paved path that leads on at the foot of the cliffs. Bob pointed us east and, in the bright sunshine it was easy to see how the red-brown Triassic rocks gave way at Beer Head to the pale Cretaceous rocks exposed by the Hooken landslip. Just visible was the distant outline of Jurassic Portland. Moving round the base of the fine grained sandstone, we poked and prodded at the rock, its smooth contours making for a most appealing tactile experience, while the low sun highlighted the bedding planes.

Sidmouth Beach

Looking east

The Strawberry Gothic architecture of Sidmouth and its beautifully kept public gardens, which looked immaculate even in December, made a pleasing backdrop for our walk. Bob pointed out the new sea defences that have been designed to protect the town from prevailing south-westerly storms. Elegantly placed piles of rock; not locally sourced but Larvikite, from Norway. It's an interesting igneous rock with a striking blue tinge, about 90% plagioclase feldspar and unique to Larvik, near Oslo. Bob mentioned that in Britain it is often called public house-ite, owing to its extensive use as bar counters in pubs. It also forms the ground floor of Harrods. Emerging into Ladram Bay, we collected a few flint pebbles and viewed the Triassic cliffs to the west, noting the characteristic gentle easterly dip. There is considerable erosion here and again the low, bright sun was helpful, highlighting the spring lines in the rock, sources of erosion. Perched on the edge of the cliffs is the thatched cottage where lived the author R F Delderfield. I hope that it is still there when you come to read this account.

At many points during our walk, Bob drew our attention to points of interest, not restricting himself to matters scientific; listening to his self effacing and amusing commentary was thoroughly enjoyable. It is clear that he has not retired in any sense - he is involved with the Norman Lockyer Observatory, (on the hills above Sidmouth) and with the new home of Camborne School of Mines, at Tremough Campus, near Penryn. Each of these establishments is an offshoot of the University of Exeter. His enthusiasm for the WHS came across abundantly and I realised with pleasure that there is so much more for me to learn in the South West of England.