In the winter of 1683-1684 the River Thames froze, between London Bridge and Westminster, to a depth of about eleven inches. The freeze began in mid-December and lasted, with brief thaws, into early February. The diarist John Evelyn went down to walk on the river on 1 January 1684 and recorded what he saw in a long passage that survives as one of the best contemporary descriptions of any Thames frost fair.
“Coaches plied from Westminster to the Temple, and from several other staires too and fro, as in the streetes; sleds, sliding with skeetes, a bull-baiting, horse and coach races, puppet plays and interludes, cookes, tipling and other lewd places, so that it seemed to be a bacchanalian triumph, or carnival on the water.”
The freeze of 1683-84 was the deepest of any in London’s recorded history and the most elaborate of the Thames frost fairs. There would be at least seven more — major ones in 1716, 1739-40, 1788-89, 1813-14 — and many smaller short-lived freezes besides. The last fair, in February 1814, lasted four days, included a small printing press that produced commemorative pamphlets sold to fairgoers, and featured an elephant led across the ice at Blackfriars Bridge. After 1814 the Thames never froze through central London again.
Why it froze, and why it stopped
Two things made the Thames freezable. The first was climate: the four centuries from roughly 1300 to 1850 were the coldest period of the last several millennia in northern Europe, a span now known as the Little Ice Age. Average winter temperatures in southeastern England during these centuries were two to three degrees Celsius colder than they are now. Some winters dropped 5 degrees below the modern average. These were freezing winters.
The second was Old London Bridge. The medieval bridge — completed in 1209, the only bridge across the Thames in London until 1750, lined with houses and shops along its 270-meter span — had nineteen narrow stone arches with massive piers and water mills wedged between them. Its piers acted as an immense breakwater, slowing the river’s flow upstream and reducing the tidal range. The water above the bridge moved slowly, was largely tidally isolated, and was shallower than the natural channel. Shallow slow-moving water freezes; deep fast-moving tidal water does not.
When a hard winter combined with Old London Bridge, the river upstream froze. The river below it — past the bridge, in the deeper, tidal Pool of London — did not. The frost fairs always took place between Westminster and the Bridge.
Old London Bridge was condemned in 1820 — too narrow for modern traffic, structurally unsound, perpetually causing river accidents — and demolished between 1825 and 1831. It was replaced by a new bridge designed by John Rennie with five much wider arches and far less obstruction to the river. The new bridge opened in 1831. The Thames, freed from its medieval dam, began flowing faster. The tidal range increased. The river became deeper, colder, and harder to freeze.
The Little Ice Age also ended in roughly the same decades. By the 1850s, the average winter temperature in London had risen by about a degree Celsius. The combined effect was that even severe winters no longer produced a freezable Thames. The river has not frozen across central London since 1814.
What survived
A few prints from the 1814 fair survive in the London Metropolitan Archives. They show a tent city on the ice with about twenty stalls labeled City of Moscow, Wellington, Free of Frost, and so on. One large stall is roasting an ox on a spit, in keeping with the fair’s traditional centerpiece — the oxen-on-ice tradition went back to at least 1564. The printing presses that operated on the ice produced small souvenirs — single-sheet broadsides with the buyer’s name, the date, and a verse — and a few examples survive in private collections. They sell at auction, when they appear, for several hundred pounds each.
The fairs are gone. The bridge is gone (a smaller version of Rennie’s 1831 design now stands at the original site; the granite blocks of the 1831 bridge itself were sold to an Arizona businessman in 1968 and reassembled at Lake Havasu City). The Little Ice Age is over. The Thames at London Bridge, on the coldest morning of the year, runs at about four degrees Celsius and does not stop.