Fort Whoop - Up Fort Whoop - Up was the nickname ( that was eventually adopted as the official name ) given to a whisky trading post , originally Fort Hamilton , near what is now Lethbridge , Alberta . During the late 19th century , the post served as a centre for various illegal activities . The sale of whisky was outlawed but , due to the lack of a police force in the region at the time , many whisky traders had settled in the area and taken to charging unusually high prices for their goods . Fort Whoop - Up is also the name of a National Historic Site in Indian Battle Park , home to the largest period firearm collection in Canada . History . Fort Hamilton was first built in 1869 by J . J . Healy and A . B . Hamilton — two traders from the Fort Benton area of Montana — to serve as a trading post . Its first structure was destroyed by fire within a year of its construction ; whether this was an accident or deliberate arson is unknown . A second , more sturdy structure later replaced the first Fort Hamilton , and was later nicknamed " Fort Whoop - Up " . It took two years to build at a cost of $ 25 , 000 . It was located at the junction of the Belly ( Oldman ) River and the St . Mary ' s River , south of where the Fort Whoop - Up National Historic Site is located . One type of alcohol sold by the Whoop - Up bandits was known as " Whoop - Up Bug Juice " , a highly prized alcohol spiked with ginger , molasses , and red pepper . It was then coloured with black chewing tobacco , watered down , and boiled to make " firewater " . It is commonly thought that the only purpose for Fort Whoop - Up was to trade whisky . Although it was one of the most infamous of the whisky trading posts , there was much more legal trading that occurred here ( e . g . trading of furs for blankets , food , firearms ) than there was trading of whisky . The outlaws of Fort Whoop - Up and surrounding areas — combined with the supposed flying of an American flag over Canadian territory — contributed to the formation of the North - West Mounted Police . Fort Whoop - Up was a destination on their march west in 1874 . The NWMP arrived at Fort Whoop - Up in October 1874 , with the task of establishing Canadian sovereignty in the territory and controlling the alcohol trade . They found no whisky on the premises and the flag that had been reported as an American flag was inspected and found to be a trade flag for the fort ( later adopted by the City of Lethbridge as the municipal flag ) . Finding no reason to close the fort , they continued further west and the fort continued in the trade of legal goods . Their first strike on the alcohol traders came after a Native complained at Fort Macleod about a group of whisky traders who had sold him overpriced whisky . Shortly after , the North - West Mounted Police caught and fined the perpetrators , although they were not at Fort Whoop - Up at the time . Although the presence of the NWMP decreased the abundance of whisky trading , it still occurred . In 1875 , the NWMP rented a room from the owners of the fort , Healy and Hamilton , and established a post there . This arrangement lasted for at least twelve years , the fort acting as both a trading post and a NWMP post . The following year , Healy and Hamilton sold the fort to Dave Akers , who was in control of the fort almost until its demise . The fort was again burned in 1888 , the fire having started in the NWMP barracks . This fire was not as severe as only the NWMP barracks were destroyed . The fort remained in operation until it was deserted somewhere between 1890 and 1892 . It was then destroyed piece by piece until the last of it was washed away in a flood in 1915 . On 28 June 1985 Canada Post issued ' Fort Whoop Up , Alta . ' one of the 20 stamps in the “ Forts Across Canada Series ” ( 1983 & 1985 ) . The stamps are perforated 12Â½ x 13 and were printed by Ashton - Potter Limited based on the designs by Rolf P . Harder . Name . There are several theories as to why the fort was nicknamed Whoop - Up . The most prominent is that it came by a description of the illicit activities that were taking place at the fort ; that people said they were going to Fort Hamilton to whoop it up . Another theory comes from the process of getting a bull train moving over the trail . The bull whacker would walk alongside the bull train and crack his whip . This process was called whooping them up , which may have led to the naming of the trail to be Whoop - up Trail , and hence the fort as well . " Bug juice " and other names . A lot of folklore has grown up around the concept of the various forms of liquor traded in the west with the First Nations peoples . The recipes of those liquors exist mainly in the realm of folk tales , and still require some research and interpretation to bring rationality to the Whoop - Up story . But the naming of those specious and spirituous concoctions has a little more scholarship . Reconstruction . A reconstruction effort was undertaken to adapt the fort to what it was originally , based on new photographic evidence . It was built as a centennial project in 1967 . Since then , various new exhibits have been unveiled , including the Thunderchief Collection , showcasing artifacts from the local Blackfoot culture ; the Shockley Firearms Gallery ; and " Voice from the Past " , an audio program that enables visitors and school children to receive guided tours year round . Seasonal re - enactments take place in the summer involving characters from the fort ' s history , and are done in partnership with Drama Nutz Productions and Guns of the Golden West , as well as local re - enactment talent .