Cathedral House, 11 The Precincts
Canterbury, Kent, United Kingdom

Founded in 597 CE by St Augustine, this cathedral was the site of the murder of the Archbishop Thomas Becket under Henry II, and the stories told by a fictional group of pilgrims on their way here make up Chaucer's Canterbury Tales. The disposition of the buildings shows a remarkable resemblance to the Benedictine abbeys of the 12th century. The church is at the center of the monastic ensemble, and to its north lie the cloisters and group of buildings used for monastic life. On the west and east are halls and chambers devoted to guests. The crypt of this church is supposedly the largest of its kind in England.

Castle Street
Glasgow, United Kingdom

Consecrated in 1136, this tall, dark church was the only Scottish cathedral to survive the Reformation unscathed. As mobs ravaged the country looking for ornamentation to demolish, Glasgow's trade guilds armed themselves to defend their prized cathedral. The result is this exceptional exemplar of Gothic architecture. Enter the church and your eyes are drawn down the 87-meter (285-ft) length of the nave, and upward to the wooden roof, some of whose timbers date back to the 14th century. Don't miss the decoration in sculpture, woodcarving, and stained glass. Look out for birds and branches-both references to the city's patron saint, St. Mungo, who preached across the British Isles and once made a pilgrimage to Rome. The Millennium Window, installed in 1999, is also splendid-a glass triptych in sapphire blue.

Candlemaker Row
Edinburgh, United Kingdom

Named after the Franciscan friars once based here, Greyfriars Kirk was built using stones from a nearby Dominican convent. It held its first service on Christmas Day 1620. Oliver Cromwell used the kirk as a barracks during his invasion of Scotland in the 1650s. In 1679, 1,200 Scottish Covenanters were held captive here. Many of these Presbyterian campaigners, opposed to London-based King Charles I's prayer book, died of starvation in the frosty churchyard. But against these grim tales, a sweeter one survives. Look outside the church for the statue of Greyfriars Bobby, a Skye Terrier so devoted to his policeman master that he stayed by his grave for 14 years.

Union Street
Aberdeen, United Kingdom

The intriguing history of the "Mither Kirk," or Mother Church, represents in brick and stone the story of Aberdeen. Parts of this edifice date back to the 12th century, although the building was not completed until the 16th century. As with other Scottish churches, the Reformation proved damaging to St. Nicholas Kirk; in 1574 the city fathers ordered the church to destroy its organ, fearing that the music would distract congregations from godly worship. In 1745, the church suffered again, when "Butcher Cumberland," the general whose army killed the Jacobite dreams of Bonnie Prince Charlie, stabled his horses in the kirk. Ten years later, the church governors put their foot down again, banning a visiting choir from performing and forbidding music "in all time coming." Look out for the elegant nave design by James Gibbs, the celebrated church architect who gave the plans to his hometown for free.

Victoria Street
Manchester, United Kingdom

Built in the late 15th century under the wardenship of James Stanley, Manchester Cathedral is filled with beautiful decorations, furnishings, and objets d'art. Its nave roof supported by minstrel angels is a classic example of perpendicular gothic architecture. Its mercy seats date back five centuries and are considered some of the finest in Europe. The huge bells, which weigh nearly a metric ton, are rung every Sunday, a quite overwhelming and amazing experience for visitors. Refresh yourself in the one-of-a-kind restaurant built into the medieval-era Hanging Bridge, a building that was not publicly displayed for 100 years. Admission to the cathedral is free, but donations are welcome. You can book a tour guide in advance of your visit.

6 The Close
Salisbury, Wiltshire County, United Kingdom

This Anglican cathedral, designed by Sir Christopher Wren in 1675, incorporates a single architectural style, early English Gothic. Built of limestone quarried from Chilmark and Purbeck, the church has the tallest spire in the UK, the largest cathedral cloister in England, and the oldest working clock (1386) in England. Other firsts include the first to have a girls' choir (1991). The octagonal chapter house has a central pillar and decorative frieze depictions of Adam and Eve, Noah, Abraham, Isaac, and Jacob. The chapter house also preserves one of the four surviving original Magna Cartas from 1215. The cathedral has been extensively painted by John Constable and was featured in William Golding's novel >em>The Spire.

Donegall Street
Belfast, United Kingdom

Home to the biggest Celtic cross in all of Ireland as well as a number of beautiful mosaics and stained-glass windows, this Anglican cathedral provides the centerpiece of Belfast's Cathedral Quarter, just north of City Hall. The main structure was completed in 1925, but other sections have been added through the years, including the ambulatory in the 1950s and the Chapel of Unity and organ loft in the 1970s. Finally, in 2007, a 40-meter (131-ft) spire was added to the top of the church. The huge Celtic cross is visible along the outer north façade of the building. Go on a Sunday to catch one of two performances by the renowned Cathedral Choir.

Royal Mile
Edinburgh, United Kingdom

Not many national heritage sights encourage spitting, but this one does. Spitting on the Heart of Midlothian, a heart-shaped section of cobblestones that marks the spot of an old jail, is supposed to bring good luck. The High Kirk, dedicated to the patron saint of lepers and cripples (also Edinburgh's patron saint), played a significant part in Scotland's religious and political history. Here in 1637, street seller Jenny Geddes threw her stool at the preacher's head in rebellion against the new Anglican prayer book. Here too, fiery Protestant reformer John Knox held forth. He is buried in the churchyard, though the grave is unmarked. Inside the cathedral, look out for Robert Louis Stevenson's memorial, as well as the Thistle Chapel, a legendary Order of Chivalry appointed by the Crown (initiates include Field Marshal Douglas Haig, commando Fitzroy Maclean, and statesman Lord Mackay of Clashfern).

The Chanonry
Aberdeen, United Kingdom

For such a peaceful building, this 16th-century structure has suffered a fearful history. Its stones were cannibalized by the troops of Oliver Cromwell in 1654, with English general Monck using the masonry to fortify his castle. During the Reformation, local barons stripped the roof of its precious lead. One legend tells that the cathedral was founded on a spot where the river Don curved like a bishop's crozier. Another (sadly unsubstantiated) is that one wall of St. Machar's contains the arm of William Wallace, the Scottish hero who was executed for his resistance to the English crown. In the 19th century, several hundred years after Wallace's demise, the cathedral was restored to its full state. Today, visitors come to see the stained glass, the octagonal towers, and the celebrated ceiling with its 48 heraldic shields, celebrating kings and archbishops from the 16th century.

St. Margaret Street
Westminster, London, United Kingdom

This Anglican Church, founded in the 12th century and dedicated to St. Margaret of Scotland, is the parish church of the British Houses of Parliament (the front pew is reserved for the Speaker of the House of Commons). Although much of the original Tudor features have been retained, the church’s interior was refurbished to its present appearance by Sir George Gilbert Scott in 1877. The building and its interior are relatively austere, but the host of memorials adorning the walls lend an air of aura and grandeur to the place. Several lovely memorial windows commemorate famous personalities like Sir Walter Raleigh, John Milton, and William Caxton.

3 Castle Street
Glasgow, United Kingdom

This striking museum, named after Glasgow's patron saint, was founded in 1993 to promote understanding between followers of the world's different religions. The Gallery of Religious Life offers information on Buddhism, Christianity, Hinduism, Islam, Judaism, and Sikhism. The Scottish Gallery tells the story of how religion shaped the roots of Western Scotland, while the Gallery of Religious Art includes sculpture, stained glass, and artworks ranging from depictions of Shiva to parables of Christian saints. In a city renowned for its sectarian history (nowadays played out on the soccer field, in fierce matches between the traditionally Protestant Rangers and Catholic Celtic), this modest museum is a peaceful and educational place for families. Once you've had enough of the spiritual stuff indoors, chill out in the Japanese Zen garden outside. Take note of the architecture, a modern re-creation of the distinctive corbeled and turreted Scottish Baronial style.

St Paul's Courtyard
London, United Kingdom

This Anglican cathedral, laid out in a late Renaissance style, has been in existence from the 17th century and is the seat of the Bishop of London. The cathedral's impressive dome, inspired by St. Peter's Basilica in Rome, rises 108 meters (365 feet). The cathedral has three domes that are equally imposing and hold three circular galleries (the internal whispering gallery, the external stone gallery, and the external golden gallery) under them. Services to celebrate, mourn, or commemorate important people and events have been held since the cathedral's first service in 1697. The American Memorial Chapel, a symbol of gratitude to the American victims of World War II, stands behind the high altar.

Colmore Row
Birmingham, United Kingdom

While most renowned for its Burne-Jones stained glass windows, the cathedral itself, built in 1715, richly rewards a second look. Designed by Italian-influenced British architect Thomas Archer, it is a good example of the English baroque, built in brick and faced with stone. Unusually for a church, the name actually honors a secular individual: Robert Philips, the landowner who donated the plot upon which the church now stands. Edward Burne-Jones, the artist who created the famous windows, was born nearby. Educated at the city's much-respected King Edward VI grammar school, he intended to become a churchman, but Arts & Crafts movement legend William Morris dissuaded him from that staid occupation. His Pre-Raphaelite designs, though added late in the 19th century, lend light and color to the interior. Removed by the Birmingham Civic Society during World War II, they survived the Luftwaffe bombings that gutted the cathedral, and returned to the renovated structure in 1948.

20 Dean's Yard
Westminster, London, United Kingdom

This Gothic church, dedicated to St Peter, has been the official church of the British sovereign. Every monarch, starting with William the Conqueror (1066), has been crowned under the cathedral’s roof in a grand ceremony steeped in tradition and history. The church has also been the burial site of English monarchs, famous poets, politicians, and aristocrats. The earliest foundations of the church are traced to the Benedictine monastery founded by St Dunstan in 909. The church, as it stands now, has a cruciform plan. Its flying buttresses and nave show a strong French influence, and its ring of chapels represents the only complete chevet in England.