Originally Posted by shelgame

FWIW, here's the GPS trace of my ride around the Kenosha velodrome, recorded with Strava on my iPhone. as you can see, the trace sucks. It couldn't even match up a single full lap of the track. Not every course I ride looks like this, but this track is especially bad. Other riders using Garmin's had no such issue (so it's not just a bad location for GPS reception).

For some reason, the iPhone GPS kept trying to 'snap' me to the nearby road(s).