Ride north up and keep to the left at the first intersection you run into. There are creeks along the way for water if you bring a dog. Up to the 4wd trail crossing is ~3.5 miles and in and out to that point takes ~2 hours. You can ride far beyond that but have not myself as of yet.
Grouse Creek Vista is the trailhead.From I-5 or I-205 - take 500 East in Vancouver.500 will curve North at Fourth Plain - turn East onto Fourth Plain.Follow Fourth Plain Road to Ward Road and turn North.Follow Ward Road until NE Davis - head East. - NE Davis turns into 109th St.At 4-way stop at 212th Ave - head North.At NE Powell Road - turn East. - Powell Road will turn into Rawson Road.Rawson Road will lead onto gravel and you will be on gravel for ~15 miles.You will reach a major fork in the road - keep left.Eventually, you will pass Larch Mountain Honor Camp(~5 miles in on the gravel road).After the camp - keep right on primary road forks you encounter and you will end up at Grouse Creek Vista Trailhead(~7 miles from honor camp).
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