Despite their small size, the British Isles provide a varied cruise experience. Beautiful coastlines are punctuated by gateway ports that lead to castles and stately homes rich in culture and heritage, rolling green countryside, the dramatic mountain landscapes of Scotland and north Wales, traditional pubs and exciting capital cities like London, Edinburgh and Cardiff.

First, what's in a name? The British Isles is the geographical term that includes Great Britain (England, Scotland, Wales) and all the offshore islands, including Ireland. (This only refers to geography, not nationality.) Outlying islands include diverse destinations like the Isle of Man, off northwest England; the Outer Hebrides, the Orkney Isles and Shetland Isles, off Scotland; and the Channel Islands, self-governing British Crown dependencies near France.

A cruise offers a hassle-free and enjoyable way of seeing some of the British Isles' best features, eliminating the need for lengthy and tiring road and rail journeys or domestic and short-haul flights with baggage weight restrictions. Unlike many other cruising destinations, the compact nature of the British Isles means you'll never have more than two sea days on longer cruises, with a maximum of one day at sea on shorter itineraries. This leaves plenty of time onshore to explore the ports of call.

Best Time for British Isles Cruises

Britain is a year-round destination with four distinct seasons. Spring (March, April and May) is generally mild and a beautiful time to see the countryside in full bloom and to visit towns and attractions when they're less crowded. Summer (June, July and August) is the peak vacation period with the warmest weather. Days are long from May until late summer, with darkness falling well after 9 p.m. Fall (September, October and November) sees the countryside lit up with orange, red and yellow tints, and winter (December, January and February) may be the coldest season but still offers Christmas markets and seasonal events at many tourist attractions (plus good-value January sales in the cities).

Summer temperatures can reach 90 degrees F but generally average 70F. In winter, temperatures can drop below freezing with some snow, mostly in northern England and Scotland, although the average temperature is around 38F.

British Isles Cruise Lines

Midsize and small ships dominate the British Isles cruise market. Southampton, Britain's largest cruise terminal, offers the widest choice of itineraries and is home to Cunard Line and P&O Cruises, which offer a classic British cruise experience. Fred. Olsen Cruise Lines also operates a large number of cruises from Southampton. Other main departure points include Dover and Tilbury, the latter just 25 miles from London. A small number of ships sail from the River Thames in the heart of London, offering a spectacular embarkation point.

Thomson Cruises offers U.K. itineraries at the value end of the market, while upscale lines include Hebridean Island Cruises, specializing in luxury small-ship sailing around Scotland and the Scottish isles, and Silversea, which offers a round-Britain voyage. Other lines operating cruises around the British Isles include Celebrity Cruises, Cruise & Maritime Voyages, Saga, Swan Hellenic and Voyages of Discovery.

British Isles Cruise Itineraries

Typically covering 14 nights, a round-Britain cruise will appeal to passengers making the cruise the main focus of their vacation. For those looking to add a cruise to a land-based stay in Europe, or a visit to friends and family in the U.K., there are shorter itineraries starting from three nights.

Northern Mini-cruises: Lines like Thomson offer three-night voyages departing from Liverpool, sailing around the north of Scotland to Rosyth or Leith for an excursion to the capital Edinburgh, before continuing down to England and disembarking at Newcastle.

Scotland: It's famous for dramatic landscapes of lochs, mountains and moorland, coupled with a fascinating history. Seven-night Scotland trips with companies like Hebridean Island Cruises take in inspiring destinations, including the Isle of Jura, where the 200 residents are outnumbered by more than 5,000 deer, and Skye, famous for its connection with Bonnie Prince Charlie.

Round-Britain: Most of the lines offer eight- and nine-night itineraries that circumnavigate Britain and include a visit to one or more outlying islands. For example, Saga's cruise from Dover takes in Ireland and Wales with ports of call at Dublin, the lively Irish capital with attractions like the Guinness brewery; Northern Ireland's Belfast, with its maritime history; and Holyhead, on the Isle of Anglesey off the tip of Wales, where Prince William and Kate Middleton used to live. The majority of weeklong cruises visit the Channel Islands, which are closer to France than England and have a very distinctive character of their own. Similarly, the Isle of Man, located in the Irish Sea, has its own currency and Manx language (although everyone speaks English).

British Isles: A 13- or 14-night itinerary, generally departing from Southampton or Portsmouth, covers all the highlights. Following the east coast, cruises sail north to Edinburgh and the Scottish Highlands, which are home to fabulous castles, before moving to the Orkney Islands and Glasgow on the west coast. Sailing south to Liverpool, these itineraries will then take in Dublin and Cork, where passengers can kiss the legendary stone at Blarney Castle to be blessed with the gift of eloquence. Cruises often continue to outlying islands like the Isles of Scilly, a cluster of islands off the Cornish coast that have some of the highest concentrations of prehistoric remains in Britain. Other itineraries include the Channel Island of Guernsey, with its charming capital St. Peter Port, and the fascinating small sister island of Sark, which is free of traffic, apart from tractors and the horse-drawn carriages that provide its main form of transport.

British Isles Cruise Port Highlights

Encapsulating the diversity of the British Isles, ports of call range from major cities on the U.K. mainland to small islands with villages fit for a picture postcard.

Belfast. Famous as Titanic's birthplace, the spectacular Titanic Belfast is a six-story visitor attraction next to the slipway where the liner was built. A tour can be combined with a visit to SS Nomadic, Titanic's tender and the world's last remaining White Star Line ship. Shore excursions visit the Giant's Causeway, a geological phenomenon caused by volcanic eruptions (although some say the coastal basalt columns were the work of a giant called Finn McCool). Back in Belfast, see the murals on the Belfast peace wall, and have a drink in the ornate Victorian Crown Liquor Saloon.

Edinburgh. A UNESCO World Heritage Site, split between the medieval old town and the Georgian "new town," the capital of Scotland is overlooked by imposing Edinburgh Castle. (Every day, except Sunday, listen for the "One O'Clock Gun," first fired in 1861 as a time signal for ships on the Firth of Forth.) The grand Royal Mile leads to Holyrood Palace, the Queen's official Scottish residence, and shore excursions include visits to the beautiful royal yacht Britannia, now permanently birthed in Edinburgh's historic dockyard.

Glasgow. Culture-rich Glasgow, with its legacy of buildings by renowned Art Nouveau Scottish architect Charles Rennie Mackintosh, has more than 20 museums and galleries, including the new Riverside Museum, housing a world-class transport collection. You'll also find the Kelvingrove Art Gallery and Museum, Scotland's most popular free attraction. A landmark of Glasgow's shipbuilding past is the giant Titan crane on Clydeside, where visitors can enjoy spectacular views from the 150-foot-high viewing platform.

Liverpool, England. It's the home of The Beatles, where fans of the Fab Four can take a tour around famous locations that include the Cavern Club, where they once played. Albert Dock, on the waterfront, is part of the city's UNESCO World Heritage site and home to the U.K.'s largest group of Grade I listed heritage buildings, including the iconic Liver Building at Pier Head. Attractions include the Merseyside Maritime Museum, thought-provoking International Slavery Museum and Tate Liverpool art gallery.

London. Royal palaces, world-class shopping and colorful districts packed with character are just some of the things that make London great. Many of the top museums and galleries, including the British Museum, National Gallery and Tate Modern are free, and the poignant Imperial War Museum underwent a huge redevelopment to coincide with the First World War centenary. A Thames river cruise is a wonderful way to see all the main sights, including Tower Bridge, the Tower of London, Big Ben and the Houses of Parliament. Visitors can hop on and off at Greenwich, home of the Cutty Sark, the last surviving tea clipper.

Newcastle. In recent years Newcastle, on the north bank of the River Tyne, and Gateshead, on the south bank, have been transformed into a single cultural and cosmopolitan visitor destination. The twin cities are linked by seven bridges, including the pioneering Millennium Bridge, known locally as the "blinking eye bridge" because of the way it tilts to allow ships to pass. From Newcastle, cruise passengers can also visit "The Angel of the North," Britain's largest sculpture, which stands 66 feet tall with a wingspan of 177 feet.

Orkney. Lying off the northeast coast of Scotland, Orkney is an archipelago of about 70 islands renowned for a wealth of archaeological sites and birdlife. Of the 20 inhabited islands, Mainland Orkney is home to the majority of the population. The capital, Kirkwall, has Britain's most northerly cathedral founded by the Vikings, a whisky distillery and attractive arts and craft shops. Orkney's geological marvels include "The Old Man of Hoy," a 450-foot sea stack formed by cliff erosion.

Southampton. One of Britain's most historic ports, the SeaCity museum traces Southampton's connection with all things maritime, including the Titanic, which set sail from the port on its doomed maiden voyage in 1912. The old town includes the 800-year-old Bargate, once the main entrance to the town, and 15th-century Tudor House, a timber-framed medieval merchant's home. When it's time to shop, WestQuay is a modern mall overlooking Southampton's tidal estuary.

Tilbury. Located on the River Thames, Tilbury is the principal port for London and just 25 miles from the city center. While the majority of cruise passengers head straight to the capital, Tilbury has an impressive fort that was built in the 16th century to defend London from an attack by sea. It was there that Queen Elizabeth I rallied her army to face the Spanish Armada. From Tilbury, visitors can go on a Downton Abbey daytrip, stopping off at Bampton in Oxfordshire, which poses as Downton village on the TV show, before visiting Highclere Castle, the main filming location.

Tobermory. Built as a fishing port in the late 18th century, Tobermory is now the main town on the Scottish Isle of Mull. The waterfront is lined with brightly painted cottages, and whisky enthusiasts can visit the distillery, founded in 1798, which produces a single malt. Mull is a premier wildlife-watching destination, and visitors might be lucky enough to catch a glimpse of rare golden and white-tailed eagles. Cruise passengers can also take boat trips to spot whales, dolphins and seals, which feed in the seas off the island.

British Isles Cruise Tips

Pack for the weather. British weather can be unpredictable. Whatever the season, there's always the chance of a rain shower, so don't forget to pack an umbrella or purchase an inexpensive one upon arrival. Onboard dress codes -- casual by day and more formal in the evenings with some lines, such as Cunard -- will be advised by the line. For shore excursions, pack layers, an outdoor jacket and comfortable shoes.

Consider school holidays. If you prefer to travel in the company of other adults, check out British school vacation and half term dates in advance. While holiday dates can vary slightly from school to school, the main summer vacation time is July and August. Alternatively, book with adult-only lines like Saga. Child-free ships include P&O Cruises' Oriana and Cruise & Maritime Voyages' Marco Polo. Hebridean Island Cruises does not accept children under the age of 9, and Swan Hellenic, which specializes in an in-depth cultural experience, naturally tends to attract adults and has no facilities for children.

On-land tipping isn't expected in the U.K. Cruise lines will advise on the onboard policy, but on dry land, tipping isn't the same way it is in the U.S. It's not customary to pay a gratuity for fast food, self-service or a takeout meal. In coffee shops, tipping is not usual, although you can leave £1, or your change, in appreciation. In restaurants, it's customary to leave 10 to 15 percent of the bill. However, check your tab carefully as some restaurants automatically add a 12.5 to 15 percent service charge, and if you don't spot this you'll end up tipping twice.

Bartenders in pubs and bars don't expect to be tipped. However, if you've developed a rapport with the bartender or have received exceptional service, you can show your appreciation by saying "and one for yourself," which is an offer to buy him or her a drink. Usually the bartender will take the money as a gratuity, rather than pouring a drink.

Know the onboard currency. Depending on the heritage of your cruise line, onboard currency could be the British pound or the U.S. dollar. For instance, folks cruising on a British line like P&O or Thomson will find onboard charges reflected in British pounds. Those sailing on American lines, such as Celebrity or Silversea, will pay bills in U.S. dollars. å