Pete's is an experience for a non-Albertan going through Cow town. On our summer vacation we did our research and found that Pete's was an institution. Not being natives of Calgary we had our doubts if the mystique of the drive-in could pass muster. Simply put it did.
Now not to attract the attention of locals who might otherwise be angry with the post, but we did not indulge in the burgers, although our friends did. The burgers seemed fine, if average, but the shakes... ooooooohhh the shakes, now that is the reason for a visit.
The shakes, to our best guess, are made with the store's soft-serve ice cream, which gives them the consistency of wall filler (that's a good thing). They were so thick that it required effort to get the lactose overload into one's mouth, but the reward... tremendous. They have a multitude of flavors and if you ask nice they will mix them together, no extra charge. I had coconut, chocolate, and cherry. It was like haveing a German chocolate cheescake milkshake.
Also, I would recommend the onion rings: they are very thin, very crisp. The batter is more crunchy than others I've had, and I like them that way. For those who like the extra thick, supersized rings, look elsewhere.
Things that you should note:
1) It is always busy, and I do mean always; an hour line-up on a hot Saturday is not uncommon. Suggest parking next door; get out of the car and go to the walk-up.
2) They are cash only, no Visa, no debit, so no cash, no food.
3) It is a task to finish a whole shake. They come in one size, and I, at 6'7" 240 lbs, got through 4/5 of it.