The Hollinger Gold Mine was discovered on October 9, 1909, by Benny Hollinger, who found the gold-bearing quartz dike that later became known as Hollinger Mines. With his friend, professional prospector Alex Gillies, Hollinger had travelled to the Porcupine region in the wake of the Wilson expedition, which had recently discovered the future Dome Mine site. Hollinger and Gillies staked three claims each, and one for their former partner, Bernard "Barney" P. McEnaney, who had been unable to join them due to severe sciatica.

The David Dunlap Observatory (DDO) is an astronomical observatory site in Richmond Hill, Ontario, Canada. Established in 1935, it was owned and operated by the University of Toronto until 2008. It was then acquired by the city of Richmond Hill, which provides a combination of heritage preservation, unique recreation opportunities and a celebration of the astronomical history of the site. Its primary instrument is a 74-inch (1.88 m) reflector telescope, at one time the second-largest telescope in the world, and still the largest in Canada. Several other telescopes are also located at the site, which formerly also included a small radio telescope. The scientific legacy of the David Dunlap Observatory continues in the Dunlap Institute for Astronomy & Astrophysics, a research institute at the University of Toronto established in 2008.