The United Kingdom pavilion opened with the rest of World Showcase on October 1, 1982. When the pavilion opened, it featured one restaurant (the Rose & Crown) and six shops: The Tea Caddy, the Queen's Table, the Biscuit Barrel, His Lordship, Pringle of Scotland and The Toy Solider .
The first change to the United Kingdom pavilion came in 1986, when the Biscuit Barrel became Country Manor . Although the shop’s name was changed, its merchandise remained essentially the same. Then, in the late 1980s the Country Manor was renamed the Magic of Wales, and His Lordship was renamed Lords and Ladies  . Subsequently, in 1995 Lords and Ladies was renamed The Crown and Crest .
The next major change in the United Kingdom pavilion came on October 1, 1999, when Harry Ramsden Fish & Chips House opened. The new dining location was a counter service restaurant which (as its name suggested) specialized in fish and chips. Since the millennium, there have been two major alternations to the pavilion. In the early 2000’s, Pringle of Scotland was renamed the Sportsman Shoppe. Then in 2006, Harry Ramsden Fish & Chips House was renamed Yorkshire County Fish Shop .
On August 25, 2019, Disney announced that the United Kingdom pavilion would be receiving a new Mary Poppins themed expansion . As part of this new area, guests will travel down Cherry Tree Lane, where they will enter the home of the Banks family and the attraction will begin <"ref name="magic"/>.
On July 15, 2020, Disney announced that the construction of the Mary Poppins attraction, intended as an expansion of the United Kingdom pavilion, would be delayed 
Although the pavilion was not home to an attraction, the original plans for the United Kingdom called for an attraction to eventually be constructed. The July 1975 edition of Eyes and Ears noted that there was room for expansion behind the pavilion, describing a corresponding piece of concept art:
Early Concept Art for the United Kingdom pavilion. This art showcases the Crystal Palace restaurant that was planned but never built.
By 1978 however those plans seemed to have once again changed, as the companies 1978 annual report noted that the pavilion would feature a "200 seat theater with a British travelogue film" .
Prior to EPCOT Center's opening, Imagineers had new plans for the Untied Kingdom pavilion. Plans now called for a Victorian building to be built in the pavilion's rear . The building (which was going to be modeled after London’s lost Crystal Palace) would have housed a live comedy show . A description of the unbuilt attraction was given in the 1982 book “Walt Disney’s EPCOT: Creating the New World of Tomorrow”:
Although nothing would come of these earlier plans, in the late 1980s/early 1990s, Imagineers created designs for a new area in the United Kingdom called The Enchanted Forest. This area would have housed topiaries of scenes from Mary Poppins, Robin Hood,  Alice in Wonderland and Winnie the Pooh . While inside The Enchanted Forest guests would also have meet and greet opportunities. Although not an attraction per say, The Enchanted Forest would also have included the "Door-Knob Tunnel" , "Cheshire Cat Maze" , and "Prince John's Castle Interactive Play Area". Finally, the area would have also housed facades of the English Parliament and Big Ben. The end of the area would be Mousterpiece Theatre, where entertainment would be found .
A look down a street in the United Kingdom pavilion. Photo by Jeff Kays
In order to show guests as much of the United Kingdom as possible, Imagineers made sure that each structure in the United Kingdom pavilion represented a different era. The center of the pavilion is known as Britannia Square. Modeled after the different town squares found in the UK, Britannia Square is where guests can find various shops and dining establishments, including the Rose & Crown. The Rose & Crown serves as both a restaurant and a pub, where guests can get a traditional British meal.
Across from the Rose & Crown, guests can visit The Tea Caddy. This shop was inspired by the childhood home of Anne Hathaway (William Shakespeare’s wife). Inside, guests can purchase teas, coffees, and hot chocolates made by Twinnings. Across from The Tea Caddy, guests can find another shop, The Queen’s Table. The store features Elizabethan architecture typical of the 1600s, and inside guests can buy tea, tea sets, and dinnerware. Behind the Queen’s Table is an English garden which features various “homes” that look out into the foliage. These homes were inspired by the houses in Disney’s Marry Poppins, and guests can often find meet and greet characters such as Alice (from Alice in Wonderland) and Marry Poppins here.
The back of the United Kingdom pavilion is themed to look like the residential section of a town set in the 1800s. This area is known as Tudor Land and is home to the Lords and Ladies shop. This boutique sells clothes and fragrances for both men and women. Another section of the town, “Upper Regency” is home to various houses with late Georgian architecture. Within the houses, is the pavilion’s Kidcot station, where Winnie the Pooh sometimes makes appearances. The houses themselves look out into a replica of Hyde Park which features a hedge maze based on the Somerleyton Hall Maze.
The final section of the United Kingdom pavilion features a city gate, inspired by the gates built during the middle ages. After passing through, guests can enter the Toy Soldiers shop. As its name would suggest, the store specializes in English games and toys. Another store, The Crown and Crest can be found nearby. The Crown and Crest is based on Sir Walter Scott’s Abbotsford Manor, and inside (besides just purchasing British merchandise) guests can look up their families’ coat of arms. Nearby, a castle called the Hampton Court Palace can be found. The palace is typical of one built during the late dark ages, and inside guests can visit the Sportsman’s Shoppe, which sells various British sporting merchandise.
Crown and Crest- This store is actually two different shops joined together. One of the shops (the Crown) sells Beatles and Epcot souvenirs, while the other (the Crest) allows guests to look up (and even purchase) their families’ coat of arms.
Sportsman Shoppe- Located within the Hampton Court Palace, this shop sells English sporting merchandise.
Queen's Table- Located near the Rose & Crown, this shop specializes in tea and tea accessories.
The Tea Caddy- Located across from the Queen's Table, this shop sells tea, candies and chocolates.
The Toy Solider- At this store guests can purchase a Paddington Teddy Bear among other toys.
Originally, Imagineers wanted to put a statue in the center of the square, and while many different famous Brits were considered including: kings, queens, Lord Nelson, Lord Byron, Robert Burns and William Shakespeare, Imagineers eventually decided to place a sundial there .
The music played in the United Kingdom pavilion includes selections from Gilbert and Sullivan and Greensleeves.
Imagineers tinted the top of the UK pavilion's chimneys to make it look like they are in use .
The United Kingdom pavilion features three classic red phone booths .
Outside of the Rose and Crown, guests can find a recreation of a lock found on the Grand Union Canal.
The lock located outside of the Crown and Rose was at one time surrounded by gates. The gates however have since been removed.
In the windows of the Hampton Court Palace, guests can see the crosses of St. Andrew, St. George and St. Patrick who are the patron saints of Scotland, England, and Ireland respectively .
A sign near the Rose & Crown Lock notes that Thomas Dudley is the lockkeeper at the Rose & Crown Lock. Dudley was the governor of the (English) Massachusetts Bay Colony in the mid-1600’s .