The City of Edmonton is celebrating the launch of a new 10-kilometre river valley trail with a treasure hunt that starts Saturday.

Edmontonians have the chance to win a "key to the city"—or a set of four $500 city attractions and recreation gift cards—in a week-long contest called the Quest for the Golden Key.

At 4 p.m. on Saturday, and then at 9 a.m. every following day until Sept. 14, the City will release clues leading to the prize.

As the story goes, Alberta's Legislature was opened in 1912 by the Governor General with a key made of gold found in the North Saskatchewan River valley. The key later disappeared, and Edmontonians have been tasked with finding it.

The eight daily clues will lead players along the Commonwealth Walkway, a new river valley pathway that runs from Groat Road Bridge, around the Legislature and across the Walterdale Bridge, to the Funicular.

Edmonton's Commonwealth Walkway is part of a collective 1,000 kilometres of trail in 100 Commonwealth cities. Throughout the 1,000 kilometres, 2,000 points of significance are marked for users to learn more about Commonwealth history.

The walkway is dedicated to the Queen, and is part of an initiative of a UK-based charity that works to create paths around the world.

It's just the second walkway of its kind in Canada, with the first commonwealth walkway popping up in Banff in 2017.

The game is free to play. On each day, the clue will lead players to a key card containing a combination number. In order to win, contestants will need to open a seven-digit combination lock.

Players have been warned they will not need to dig, climb, open or move objects to find the key cards, nor will they be hidden on private property or dangerous locations.

Find the full game rules online.

Commonwealth Walkway users can also download an app, which pinpoints the 60 historical markers, for an interactive experience.