Cannon Hill Park was originally home to a brickyard. Henry Brook discovered a clay deposit in the 1880s and it was used for making bricks. Cannon Hill bricks were widely used in downtown buildings as the city rebuilt after the Great Fire of 1889. The company also produced paving bricks, many of which are still in place on South Hill streets, though now covered with asphalt. The clay soon ran out, however, and the brickyard closed, leaving a shallow depression behind.
The park was originally named Adams Park because the land was owned by John Quincy Adams' grandson. It was changed to Cannon Hill Park for A. M. Cannon, local banker and real estate developer.
When the Olmsted Brothers came to Spokane in 1907, they left Spokane with a design complete with a stone shelter, two pergolas, and a children's wading pool. The wading pool was easy to construct as the depression left by the brickyard left a natural pool, shallow enough to play in to cool off in the summer and freeze for ice skating in the winter. It was recommended in the Olmsted Brothers' report that, "this park should be refined and pretty and adapted to quiet recreation on the assumption that the larger boys of the neighborhood can easily walk to Manito Park for ball games and other sports."