The headland is the key to Scarborough. A Norman castle was established on the high cliff in the twelfth century, defending against the Scots and against piracy. The town grew up first along South Bay, sheltered by the headland from the northeasterly gales that lash the coast in winter. The harbour is here, the original fishing fleet, the Spa complex, the Luna Park funfair, the amusement arcades, donkey rides, fish and chip shops - everything the postcards show. North Bay, on the other side of the headland, was the Victorian and Edwardian extension - quieter, more residential, with the long Open Air Theatre and the boating lake of Peasholm Park. Both bays are broad sandy beaches that almost disappear at high tide. The Cleveland Way coastal footpath crosses the headland between them.

Scarborough exists in its strange location partly because of the River Derwent, which does something no other British river does: it rises within sight of the North Sea but flows the wrong way. Carved by Ice Age mud deposits that blocked the natural eastward course, the Derwent now runs inland for seventy miles, between the North York Moors and the Yorkshire Wolds, before finally meeting the tidal Humber at the south. The Wikivoyage editors call this the River Niger of Yorkshire, with Malton as its Timbuktu - a fair comparison. The Derwent valley was the natural transport corridor inland from the coast: traders heading to the medieval Scarborough Fair came that way, as did marauding armies of Normans, Scots, Royalists and Parliamentarians at various dates. In 1804 a partly artificial channel called the Sea Cut was completed to manage the river's flow.

Among the unexpected things in Scarborough is Anne Bronte's grave, in the churchyard of St Mary's at the foot of the castle headland. Anne, the youngest Bronte sister, came to Scarborough in May 1849 hoping the sea air would arrest her consumption. She had been here twice before with her family on holidays. She lasted three days. She died on 28 May 1849 at the lodging house and was buried here rather than at Haworth - her sister Charlotte, who had accompanied her, decided to spare their father a second funeral after Emily's death the previous year. The grave is regularly visited by literary pilgrims. A stone in the churchyard, with its slightly inaccurate dates (corrected later by Charlotte), is reached by walking up the steep path beneath the castle. Scarborough also features in Anne's novel The Tenant of Wildfell Hall, where it stands in for an idealised seaside refuge.

In June 1993, the Holbeck Hall Hotel - a substantial Victorian seafront establishment on the South Cliff - collapsed into the sea over the course of about forty-eight hours, live on television news. The cause was not erosion in the usual sense; the cliff itself slumped after weeks of heavy rain liquefied the subsoil, which then landslipped down toward the beach. The hotel went with it. No one was killed - the guests had been evacuated. The grassy bank that remains is now marked by an information board and, in the gentle deadpan of the modern internet, a Google Maps caption reading 'add a missing place'. The Scarborough coast has lost places before; what changed in 1993 was that the loss was filmed. A few hundred yards north, Scarborough Spa and Italian Gardens continue along the Esplanade as if nothing happened.

Just east of the harbour, on Vernon Road, stands a small circular building called the Rotunda, opened in 1829. It was built to house the geological collection of William Smith - the canal engineer who, while surveying coal seams in the 1790s, realised that you could identify and correlate rock strata across the country by the fossils they contained. This insight founded modern stratigraphy. Smith's nephew John Phillips designed the Rotunda specifically to display Smith's collection in correct stratigraphic order: the oldest rocks at the bottom shelf, working up to the youngest at the top. The building is itself a piece of intellectual architecture, an idea given physical form. It is still operating as a museum, paired with Scarborough Art Gallery 100 yards west in an Italianate villa on The Crescent.