When i am looking for a looooonnnnngggg walk, North Glenmore Park is the perfect solution. The loop around the reservoir is approximately 18 kms, which gives me a good 3 hour walk if I am moving brisky.
You can't beat the maintenance of the paths, or the scenery of the water and the reservoir itself. In some places, it doesn't even feel like you are in the city.
If you are doing the full loop, I highly recommend stopping at Gasoline Alley in Heritage Park for a coffee, which is approximately the half way point.
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