K-Days, formerly known as the Edmonton Exhibition, Klondike Days, and Capital Ex, is an annual 10-day exhibition held in Edmonton, Alberta, Canada mostly in late July. It runs in conjunction with the Taste of Edmonton, the Great Outdoors Comedy Festival, and – from 2006 through 2012 – the Edmonton Indy.

The exhibition, hosted by Explore Edmonton beginning 2022, and hosted until 2019 by Northlands, is held at the Exhibition Lands also known as the Edmonton Northlands Grounds adjoining Edmonton Expo Centre. K-Days begins on the third Friday of July and five days after the Calgary Stampede (until 2009, it began four days after), making it end on the Sunday of July's last weekend.

The fair was originally named the Edmonton Exhibition from its founding in 1879 until 1964 when it was renamed Klondike Days. The name change coincided with the introduction of the kitsch theme associated with the 1890s and the Klondike Gold Rush. The gold rush had taken place over a thousand miles to the northwest. Edmonton was a stopping point for prospectors headed to the Yukon Territory on the "all-Canadian overland route".

The name was changed to Capital Ex, in 2006. There was some controversy over the change in name from Klondike Days, with many locals continuing to refer to the exhibition as Klondike Days or K-Days. Ken Knowles, President of Northlands, explained that the rebranding "... was so much more than a name. It was about the programming and the opportunity to showcase the best of the region and the province". The name change was recognized at the 2007 Alberta Tourism Awards, where Knowles stated "This recognition from the tourism industry is particularly gratifying as it reinforces our ongoing efforts through Capital Ex to continue to celebrate our province and to build Alberta pride."

Before the 2012 event, Northlands announced that the Capital Ex name would be retired, and a new name would be chosen by public vote. Eventgoers chose K-Days from the six names offered. The new name for the fair was announced on July 29, 2012. The original Klondike Days name was not one of the six options available. Some fans of the event's previous name, Klondike Days, have stated that the name change to Capital Ex was a poor decision due to the region's history. Many feel that the event being renamed back to K-Days, by the overwhelming majority of the vote, shows just how much of a mistake the initial name change was.

The Edmonton Agricultural Society organized the first local exhibition on the original Fort Edmonton site on October 15, 1879. This was the first event of its kind held in what was then known as the North-West Territories. Edmonton's first fair showcased locally produced livestock, grain, vegetables, and handiwork and attracted 500 people. Calgary and Saskatoon soon started their own exhibitions in 1886 with Regina following in 1894. In 1893, the organization held the city's first spring exhibition, and in 1899, the exhibition grounds were relocated to Rossdale Flats (now Edmonton Ballpark). By 1904, the exhibition's attendance exceeded 20,000 (5,200 on opening day). During this period Arthur G. Harrison was President of the Edmonton Exhibition Association.

The first parade to promote the fair was held in 1903. However, the fair did not organize a community parade in the 1930s and 1940s.

The fair was relocated to its current site in Northlands (now named Edmonton Expo Centre) in 1910. In 1912, it was extended to six days. It continued to be held through the First World War, even though the facilities were at the disposal of the Canadian military. A similar arrangement was made during the Second World War, though this time with the Royal Canadian Air Force.