This swath of temperate rainforest a 20-minute drive from the city is bisected by the Trans-Canada but squeezes a lot of nature into its 4.5 sq km. A short 700m trail leads to Niagara Falls, which is a lot narrower but only 4m shorter than its famous Ontario namesake. Hike beyond the falls and you'll reach an impressive railway trestle (which you're not supposed to walk on).
On the other (eastern) side of the road, it's possible to hike up a more rugged path to the top of 410m Mt Finlayson (4km round-trip).
The Freeman King Visitors Centre, aka 'The Nature House,' has a wildlife cam and information on the annual salmon run.