Oh, fun topic!
Mine has to be Oregon Raceway Park. It's a small track about two hours east of Portland, OR, straight in the middle of nowhere. The course is a roller-coaster -- pretty much no straights, lots of elevation change, blind turns everywhere. There's a even a halfpipe -- a sequence of 3 turns with massive banking flowing into each other. And when the weather's good you see Mt. Hood towering behind all that. It's just a awesome driving experience. Here's a
video of me fumbling around learning the course.
Unfortunately, they don't seem to be doing too well -- the track has been
for sale for a while now. I'm sure being so remote has something to do with it.
Maybe I like it so much because the one time I went, the experience was pretty surreal. I was heading to Portland to compete in the Hood To Coast running relay. Think 12 runners stuck in a van, alternating between trying to catch up on sleep and getting off to run a leg at 5-something minutes per mile pace. Lather and repeat for 200 miles / 20 hours. Then celebrate (we did ok) and head off to the track a few hours later, sleep-deprived, sore and generally exhausted. Sling a car around the rollercoaster all day, then saddle up for a 10-hour overnight drive back to the bay area, just in time for Monday morning at the day job... Fun times.