गूफ़

Alan hides in a refrigerator after being chased by some rednecks. The rednecks shoot at the refrigerator where he is hiding, but when he emerges from the refrigerator, there is no evidence of the door being shot at, either inside or out.

The rednecks follow Alan for a long distance while leaving their car behind. When Alan hides in the refrigerator, after a short while the rednecks can be heard leaving in their car (which they actually left far away).

Alan twice sets down the envelope with the tickets in it.

The Toronto Rock and Roll Revival was held at Varsity Stadium, at the University of Toronto, September 13, 1969 with the appearance of John Lennon, Yoko Ono and The Plastic Ono Band was not publicly known in advance.

Obvious stunt car: The car that explodes is a 1959 Plymouth, not a 1960 as it is in the rest of the film.

When Alan cuts himself with the razor blade, on the coffee table is a commercially made plastic bong. The first plastic bong was patented in 1975, six years after the timeline of the movie. Prior to the mid-1970s, bongs were made of bamboo.

Enthusing over the concert, Hector exclaims "Radical!" in 1969. But this slang dates from the 1980s.

In the scene where Alan waits for the train to go past, there are "double stack" inter-modal cars on the train as well as an "End-of-Train-Unit" or "SBU" (Sense and Braking Unit, which replaced the cabooses). Both of these things came into use in the 1980s and this movie is supposed to take place in 1969.

Alan's "inner voice" says, "You are not going to Toronto with Cheech & Chong here while your mom's lying in a hospital...." The story is set in 1969 when Cheech & Chong were still unknown comics working in Canada. Their first album wouldn't come out till 1972.

The Hell's Gate ride wasn't in production in 1969. The earliest models didn't appear widely until the '80s.

As Alan Parker is heading to Lewiston, ME, he is seen walking past a sign indicating the junction of US Routes 2 and 68. US Route 68 runs for 560 miles between Reidland, KY, and Findlay, OH. The closest it comes to Lewiston is over 700 miles away.