Alan, I only fish once in a while so I really don't know, but some local sites indicate that salmon are in the river in September. Depending on your prowess with bait and lures, I'd recommend a guide to hook you up with a sure fire rig and deal with the location, regulations, licensing, etc.
My favourite and most recommended hike in the Chilliwack area is Mt. Cheam – spectacular views---but its a 9 kilometer (6 mile) round trip after a long rough drive partway up the mountain. My son would do it in 6 hours without breaking a sweat, not so much for me
Here's a list of a few of the other hikes in the area and reviews.
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