St Wilfrid, the seventh-century Northumbrian bishop who had argued for the Roman computation of Easter at the Synod of Whitby and then fallen in and out of favour with successive kings, died at Oundle in 709 AD in a monastery he had consecrated. Eddi, his chantor and biographer, calls the place Undolum in his account written around 715, the earliest documentary reference. Bede also names it. The current parish church of St Peter occupies the same site as Wilfrid's original foundation. Iron Age coins, Roman bronze pins, and fragments of a Roman cup found in the churchyard suggest the bank above the Nene had been used as a settlement for centuries before the monk arrived. The market charter dates from 972. The town hall on the market square was completed in 1830, replacing an earlier building. The Anglo-Saxon Secgan manuscript records that Oundle's patron saint, of whom very little is otherwise known, was buried in the monastery here. The chapel built for him in the eleventh century once stood on the small knoll at the end of St Osyth's Lane, and that lane keeps his name even though the chapel is gone.

The Talbot Hotel on New Street is built of stone carted four miles up the road in 1626 from the ruins of Fotheringhay Castle. The hotel had originally been timber-framed; its rebuilding in stone happened just as the castle was finally being broken up for materials. Local tradition has it that the oak staircase inside the Talbot is the same staircase Mary, Queen of Scots, walked down on the morning of her execution in February 1587, and that her ghost still uses it. The Drumming Well Room is named after a well in the yard once said to produce a drumming sound as a warning of imminent death. The Talbot is one of several old inns: the Rose and Crown is seventeenth century, the Ship Inn dates from the fourteenth century as a coaching stop, the George occupies an older building still. The Talbot's staircase is the one tourists ask about. It is sturdy oak, well worn, and is in continuous daily use by people coming down for breakfast.

Oundle's terraces are built almost entirely of local stone: warm ironstone with paler oolite for the better houses, slate roofs from Collyweston a few miles north. The Old Town Hall on the market square, the long terrace of Georgian fronts on West Street, the narrow medieval alleys behind the church all show the same palette. The town's annual rhythm includes the Oundle International Festival, founded in 1985 around a Frobenius pipe organ in the Oundle School chapel and now one of Britain's most respected summer schools for young organists; the Fringe Festival every July; a literature festival; the carnival; and the Thursday and Saturday markets. The Stahl Theatre in a converted Congregational chapel on West Street, named after the American Ronald Stahl who lived in the town around 1900, has been run since its opening in 1980 by Oundle School but used by the wider community. Daniel Radcliffe's The Woman in Black was filmed at Cotterstock Hall just to the north in 2012; the fifth season of The Crown shot in the Market Place in September 2022.

The Oundle and Ashton War Memorial stands at the junction of New Street and West Street, unveiled on 14 November 1920 by Frederick William Sanderson, the great headmaster of Oundle School. The memorial carries ninety-five names: sixty-eight from the First World War, twenty-seven from the Second. Four of those Second World War names served in the Royal Air Force, which makes sense given Oundle's position in bomber country between Wittering and Cottesmore. The bypass on the A605 was opened in December 1985 by Princess Alice, Duchess of Gloucester, and there is a brass plaque on the roundabout to commemorate the event. The railway station closed in 1972; the elegant Italianate building by John Livock survives as a private house. Oundle still has its rugby club founded in 1976, a cricket club founded in 1826 that plays in the Northamptonshire Cricket League Premier division, and three supermarkets squeezed in among the stone houses. Notable people who have called it home include Richard Dawkins, Bruce Dickinson and the actor Himesh Patel.