I'm starting my comprehensive Vancouver running track review with Brockton Oval because it's my favourite. I love going there on summer evenings after work, when it doesn't get dark until late.
It's a crappy old track in a beautiful setting, just steps away from Coal Harbour and the Seawall. Float planes coming and going from the harbour frequently pass by overhead. It's a nice distraction when you're pumping out 800s.
Brockton Oval is a dirt track with a grass playing field in the centre. There are decent washrooms and a drinking fountain on site. Unfortunately there is no lighting provided, so please take care after dark - you never know what kind of creeps are lurking in the bushes...
Here's an aerial photo showing where Brockton Oval is in Stanley Park:
You can either drive and pay $1 or $2 for parking, or take a bus. You can also ride your bike or walk if you're feeling ambitious (or live close by). Here's a map showing where Stanley Park is related to downtown:
The most people I've ever seen on the track at one time, besides me, is two. Sometimes there will be a team playing football or rugby on the field, which is nice for added security. The parking is also super close, so that's good for security too.