If you’ve ever been on The Grand National roller coaster at Blackpool Pleasure Beach, you may have noticed that it performs a very clever magic trick.

The ride tries to replicate the thrills of the Grand National horse race by having two roller coaster trains race each other round a twin track circuit.

But if you board the “blue” train on the right hand side of the station, when you have enjoyed your thrilling journey you will find yourself back on the left side of the station. The other “green” train has swapped sides with you.

But nowhere on the ride do the tracks actually cross over. So what is the secret behind this switching?

This mystery puzzled my grandfather for many years.

Every week he would collect my sister and I from school and take us to Blackpool Pleasure Beach. We would watch the Grand National from many vantage points and listen to the screams of the passengers and the roaring clatter of the trains as the rickety wooden structure vibrated and shook.

But even from high up on the Cable Car Ride, or from the observation window overlooking the “chain lift hill”, he could see no evidence to suggest that the tracks actually crossed over. And yet no matter how many times we watched the trains would always return to the station having changed sides.

Sadly the secret of the Grand National roller coaster eluded my grand father. He never found out the answer before he sadly died.

And then one day, many years later, whilst surfing the internet, a childhood memory flashed back into my mind. Could I solve the secret of the Grand National roller coaster? Of course, Google was my friend. Within minutes I had solved the mystery.

The Grand National is a wooden twin track racing roller coaster by category. Known affectionately as “The Nash” by people who grew up in Blackpool, the ride offers many moments of “airtime” that stomach churning moment of weightlessness at the top of each drop.

They built it in 1935 to the plans of respected roller coaster designer, Charles Paige. And they incorporated into the track the special feature that was to befuddle my grand father and many others for years until the internet revealed the answer.

And what is the answer? Well the Grand National is not a twin track at all. It’s only one track. The station is actually at the half way point. So after giving passengers one ride, each train has only completed half a circuit and has ended up back at the station on the other side of the boarding platform. The illusion is that they have swapped sides.

It’s called a Mobius loop.

There are only two other roller coasters in the world that do this illusion. The Racer at Kennywood in the USA, and Montaña Rusa at La Feria Chapultepec Magico in Mexico City, Mexico.

The sad thing however is that I never got to tell my grand father the secret of the Grand National roller coaster.

But I suspect he knows it by now too. And on the day I worked it out, he’ll have looked down from where ever he is, lit his pipe, and smiled.

Take a ride on the Grand National with this YouTube video from the Theme Park Review.

Your turn: Have you ever been on the Grand National roller coaster? Did you notice the magic trick of changing sides. Did you know the Secret of the Grand National Roller Coaster Blackpool? I’d love to hear your roller coaster stories. Please leave a comment or share a link to your own articles.