20 Best Sights in The Thames Valley, England

Signs warn drivers of "Boys Crossing" as you approach the splendid Tudor-style buildings of Eton College, the distinguished boarding school for boys ages 13–18 founded in 1440 by King Henry VI. It's all terrifically photogenic, with students still dressing in pinstripe trousers, swallowtail coats, and stiff collars. Rivaling St. George's at Windsor in terms of size, the Gothic Chapel contains superb 15th-century grisaille wall paintings juxtaposed with modern stained glass by John Piper. Beyond the cloisters are the school's playing fields where, according to the Duke of Wellington, the Battle of Waterloo was really won, since so many of his officers had learned discipline and strategy during their school days. Boris Johnson was the most recent of the country's many prime ministers to have been educated here. The Museum of Eton Life has displays on the school's history and vignettes of school life. From May through September, the school gives public tours (bookable online) on Friday at 2 and 4.

Founded in 1458, with a handsome main quadrangle and a supremely monastic air, Magdalen (pronounced maud-lin) is one of the most impressive of Oxford's colleges and attracts its most artistic students. Alumni include such diverse people as P. G. Wodehouse, Oscar Wilde, and John Betjeman. The school's large, square tower is a famous local landmark. To enhance your visit, take a stroll around the Deer Park and along Addison's Walk.

More than half a million intriguing archaeological and anthropological items from around the globe, based on the collection bequeathed by Lieutenant-General Augustus Henry Lane Fox Pitt Rivers in 1884, are crammed into a multitude of glass cases and drawers. In an eccentric touch that's surprisingly thought-provoking, labels are handwritten and items are organized thematically rather than geographically—a novel way to gain perspective. Give yourself plenty of time to wander through the displays of shrunken heads, Hawaiian feather cloaks, and fearsome masks. Grab coffee from the van usually parked on the grass out front. 

Attention all Muggles—this spectacular attraction just outside Watford immerses you in the magical world of Harry Potter for hours. From the Great Hall of Hogwarts, faithfully re-created, down to the finest detail, to "magical" paraphernalia beautifully displayed in the vast studio space, each section of this attraction showcases the real sets, props, and special effects used in the eight movies.

After entering the Great Hall, a fitting stage for costumes from each Hogwarts house, you can admire the intricacies of the huge Hogwarts Castle model, ride a broomstick, try butterbeer, explore the Forbidden Forest, and gaze through the shop windows of Diagon Alley. The Hogwarts Express section—at a faithfully reproduced Platform 9¾—allows you to walk through a carriage of the actual steam train and see what it's like to ride with Harry and the gang.

Tickets, pegged to a 30-minute arrival time slot, must be prebooked online. Slots fill up fast over summer and school holidays, so reserve well in advance. The attraction is a 20-minute drive from St. Albans. You can also get here by taking a 20-minute train ride from London's Euston station to Watford Junction, then a 15-minute shuttle-bus ride, free with a valid Studio Tour ticket; the shuttle runs every 30 minutes. Via car from London, use M1 and M25. Parking is free.

From William the Conqueror to Queen Victoria, the kings and queens of England added towers and wings to this brooding, imposing castle. Visible for miles—though the most impressive view is from the A332, coming into town from the south—it's the world's largest inhabited castle and the only residence in continuous use by the British Royal Family since the Middle Ages. Despite the many hands involved in its design, the palace manages to have a unity of style and character.

As you enter, Henry VIII's gateway leads uphill into the wide castle precincts, where you're free to wander. Across from the entrance is the exquisite St. George's Chapel (closed Sunday). Here lie 10 of the kings of England, including Henry VI, Charles I, and Henry VIII (Jane Seymour is the only one of his six wives buried here) along with one very famous queen; the chapel is the last resting place of Queen Elizabeth II and her husband Prince Phillip. One of England's noblest buildings, the chapel was built in the Perpendicular style popular in the 15th and 16th centuries, with elegant stained-glass windows, a vaulted ceiling, and intricately carved choir stalls. The colorful heraldic banners of the Knights of the Garter—the oldest British Order of Chivalry, founded by Edward III in 1348—hang in the choir. The ceremony in which the knights are installed as members of the order has been held here with much pageantry for more than five centuries. The elaborate Albert Memorial Chapel was created by Queen Victoria in memory of her husband.

The North Terrace provides especially good views across the Thames to Eton College, perhaps the most famous of Britain's exclusive public schools (confusingly, "public schools" in Britain are highly traditional, top-tier private schools). From the terrace, you enter the State Apartments, which are open to the public most days. On display to the left of the entrance to the State Apartments, Queen Mary's Dolls' House is a perfect miniature Georgian palace-within-a-palace, created in 1923. Electric lights glow, the doors all have tiny keys, and a miniature library holds Lilliputian-size books written especially for the young queen by famous authors of the 1920s. Five cars, including a Daimler and Rolls-Royce, stand at the ready. In the adjacent corridor are exquisite French couturier–designed costumes made for the two Jumeau dolls presented to the Princesses Elizabeth and Margaret by France in 1938.

Although a fire in 1992 gutted some of the State Apartments, hardly any works of art were lost. Phenomenal repair work brought to new life the Grand Reception Room, the Green and Crimson Drawing Rooms, and the State and Octagonal Dining Rooms. A green oak hammer-beam (a short horizontal beam that projects from the tops of walls for support) roof looms magnificently over the 600-year-old St. George's Hall, where the late Queen Elizabeth frequently hosted state banquets. The State Apartments contain priceless furniture, including a magnificent Louis XVI bed and Gobelin tapestries; carvings by Grinling Gibbons; and paintings by Canaletto, Rubens, van Dyck, Holbein, Dürer, and Bruegel. The tour's high points are the Throne Room and the Waterloo Chamber, where Sir Thomas Lawrence's portraits of Napoléon's victorious foes line the walls. You can also see arms and armor—look for Henry VIII's ample suit. A visit October to March also includes the Semi-State rooms, the private apartments of George IV, resplendent with gilded ceilings.

To see the castle come magnificently alive, check out the Changing the Guard ceremony, which takes place daily at 11 April to July and on alternate days at the same time August to March. Confirm the exact schedule before traveling to Windsor. Note that the State rooms (and sometimes the entire castle) are closed during official state occasions; dates of these closures are listed on the website, or you can call ahead to check. Admission includes an audio guide and, if you wish, a guided tour of the castle precincts. Entrance lines can be long in season, and you're likely to spend at least half a day here, so come early.

Deep in the heart of Northamptonshire sits the ancestral home of the Spencers, best known in recent years as the family home of Princess Diana. Here, on a tiny island in a lake known as the Round Oval, is Diana's final resting place. A lakeside temple is dedicated to her memory. The house has no permanent Diana exhibits, but it does have rooms filled with paintings by van Dyck, Reynolds, and Rubens—all portraits of the Spencers going back 500 years—and an entry hall that architectural historian Nikolaus Pevsner called "the noblest Georgian room in the country." Two paintings by contemporary artist Mitch Griffiths stand out in complete contrast.

On the west side of the estate park is Great Brington, the neighboring village where the church of St. Mary the Virgin holds the Spencer family crypt. It's best reached by the designated path from Althorp. The house and grounds are closed throughout the winter and open to the public in July and August. 

A vast library, the domed Radcliffe Camera, usually surrounded by tourists with cameras trained at its golden-stone walls, is Oxford's most spectacular building, constructed in 1737–49 by James Gibbs in Italian baroque style. It contains part of the Bodleian Library's enormous collection, begun in 1602 and one of six "copyright libraries" in the United Kingdom. Like the Library of Congress in the United States, this means it must by law contain a copy of every book printed in Great Britain. In addition, the Bodleian is a vast repository for priceless historical documents—including a Gutenberg Bible and a Shakespeare First Folio. The collection continues to grow by more than 5,000 items a week.

Guided tours—three to six of them daily except when private events are being held—reveal the magnificent Duke Humfrey's Library, which was the original chained library, completed in 1488 (the ancient tomes are dusted once a decade) as well as the spots used to create Hogwarts in the Harry Potter films. Standard tours can be prebooked, as can the extended tours on Wednesday, Saturday, and Sunday. Otherwise, arrive early to secure first-come-first-served tour tickets. Audio tours don't require reservations.

Passing through Carfax, the center of Oxford and where four roads meet, you can spot this tower. It's all that remains of St. Martin's Church, where Shakespeare stood as godfather for William Davenant, who himself became a playwright. Every 15 minutes, little mechanical "quarter boys" mark the passage of time on the tower front. Climb up the 99 steps of the dark stairwell for a good view of the town center.

Built in 1546, the college of Christ Church is referred to by its members as "The House." This is the site of Oxford's largest quadrangle, Tom Quad, named after the huge bell (6¼ tons) that hangs in the Sir Christopher Wren–designed gate tower and rings 101 times at 9:05 every evening in honor of the original number of Christ Church scholars. The vaulted, 800-year-old chapel in one corner has been Oxford's cathedral since the time of Henry VIII.

The college's medieval dining hall contains portraits of many famous alumni, including 13 of Britain's prime ministers, but you'll recognize it from its recurring role in the Harry Potter movies (although they didn't actually film here, the room was painstakingly re-created in a studio). Plan carefully, as the dining hall is often closed between noon and 2 during term time. Lewis Carroll, the author of Alice's Adventures in Wonderland, was a teacher of mathematics here for many years; a shop opposite the meadows on St. Aldate's sells Alice paraphernalia. The college also moonlights as a B&B in summer, renting vacant student dorms to the public at around £60 a night. 

Described by Queen Victoria as a "bijou of taste," Cliveden (pronounced Cliv-dn) is a magnificent country mansion that, for more than 300 years, has lived up to its Georgian heritage as a bastion of aesthetic delights. The house, set on 376 acres of gardens and parkland above the River Thames, was rebuilt in 1851; but it was the rich and powerful Astor family, who purchased it in 1893, that made Cliveden famous. In the 1920s and 1930s this was the meeting place for the influential salon known as the Cliveden Set—a group of strongly conservative thinkers who many accused of being Nazi sympathizers. Its doyenne was Nancy Astor, an American by birth, who became the first woman to sit in the British Parliament.

The ground-floor rooms of the house are open for short guided tours from March through September, as is the Octagon Chapel, with its beautiful gilt-painted ceiling and wall panels. You can wander the lovely property, which includes a water garden, miles of woodland and riverbank paths, a kids' play area, and a yew-tree maze. Book your timed ticket for the house beforehand or early on the day. Boat hire and trips are available daily in July and August. Note that opening times of the house can be unpredictable, even at the busiest times of the year; always call before setting out.

The Ashmolean, the world's oldest public museum, was originally housed in this 1683 building, which now holds scientific and mathematical instruments, from astrolabes to quadrants. Among the gems are a wonderful collection of 18th- and 19th-century models of the solar system and the chalkboard Einstein used in a lecture on the Theory of Relativity. There are guided tours on Thursday (2:30 and 3:15) and Saturday (12:30 and 1:15).

Founded in 1621 as a healing garden, this is the oldest of its kind in the British Isles. Set on the river, the University of Oxford's diverse garden displays 6,000 species ranging from lilies to citrus trees. There are a spacious walled garden, six luxuriant glass houses, including insectivorous and lily houses, and interesting medicinal, rock, and bog gardens to explore. Picnics are allowed, but you must bring your own food and drinks, as there's nowhere to buy them inside.

This highly decorative Victorian Gothic creation of cast iron and glass, more a cathedral than a museum, is worth a visit for its architecture alone. Among the eclectic collections of entomology, geology, mineralogy, and zoology are the towering skeleton of a Tyrannosaurus rex and casts of a dodo's foot and head. There's plenty for children to explore and touch.

Focusing on the history and sport of rowing, this absorbing museum built on stilts includes exhibits devoted to actual vessels, from a Saxon log boat to an elegant Victorian steam launch to Olympic boats. One gallery tells the story of the Thames as it flows from its source to the ocean, while another explores the history of the town and its famed regatta. A charming Wind in the Willows walk-through exhibit evokes the settings of the famous children's book.

Your imagination can take you back to AD 130 as you walk around the ruins of this 2,000-seat Roman Theater, one of the few in the country. Next to it are the scant ruins of a Roman town house, shops, and a shrine. Believed to be the "oldest producing theatre" in the U.K., you can catch shows here throughout the year.

The attractive campus of St. John's has seven quiet quadrangles surrounded by elaborately carved buildings. You enter the first through a low wooden door. This college dates to 1555, when Sir Thomas White, a merchant, founded it. His heart is buried in the chapel (it's a tradition for students to curse as they walk over it). The Canterbury Quad represented the first example of Italian Renaissance architecture in Oxford, and the Front Quad includes the buildings of the old St. Bernard's Monastery. The public are welcome to use the gardens on afternoons.

This traditional event, which dates back 800 years, takes place in Marlow during the third week of July. By bizarre ancient laws, King Charles owns every single one of the country's swans (just as his mother did before him). Each year, swan-markers in skiffs start from Sunbury-on-Thames, catching the new cygnets and marking their beaks to establish ownership. The King's Swan Marker, dressed in scarlet livery, presides over this colorful ceremony.

With exhibits on everything from food to burial practices, the Verulamium Museum, on the site of the ancient Roman city, explores life 2,000 years ago. The re-created Roman rooms contain colorful mosaics that are some of the finest in Britain. Every second weekend of the month, "Roman soldiers" invade the museum and demonstrate the skills of the Imperial Army.

Adjacent to the Verulamium Museum, this park contains the usual—playground, wading pool, lake—and the unusual, namely Roman ruins that include part of the town hall and a hypocaust, or central-heating system, that dates from AD 200 and included one of the first heated floors in Britain. Brick columns supported the floor, and hot air from a nearby fire was drawn underneath it to keep bathers warm.

Stretching up into the foothills of the Berkshire Downs between Swindon and Oxford is a wide fertile plain known as the Vale of the White Horse. Here, off B4507, cut into the turf of the hillside to expose the underlying chalk, is the 374-foot-long, 110-foot-high figure of a white horse (known as the the Uffington White Horse), an important prehistoric site. Some historians believed that the figure might have been carved to commemorate King Alfred's victory over the Danes in 871, whereas others date it to the Iron Age, around 750 BC. More current research suggests that it’s at least 1,000 years older, created at the beginning of the second millennium BC. Uffington Castle, above the horse, is a prehistoric fort. English Heritage maintains these sites. To reach the Vale of the White Horse from Oxford (about 20 miles), follow A420, then B4508 to the village of Uffington.