Did you know you can order a quesadilla-burrito hybrid at Chipotle? Or not all footlong subs are 12 inches (30cm)? There's more than meets the eye to your favourite fast food restaurants. From secret menu items to royal owners, here are amazing facts that will make your jaw drop.

You might be familiar with Domino’s drivers ringing your doorbell, but in Australia and Houston, Texas, the global pizza chain is testing delivery robots. The golf-cart-size cars are able to navigate their way to customers' homes using GPS and sensory technology.

The global sandwich chain has only been known as Subway since 1968. Prior to that, it was called Pete's Super Submarines after one of its founders, Dr. Peter Buck. He teamed up with high school graduate Fred DeLuca in 1965 when the average cost of a sub was 49 cents (39p).

That’s right, it's easier to get your hands on a Meatball Marinara than a Big Mac or a Frappuccino. Subway had 41,600 restaurants in 2019, making the sandwich giant the largest chain in the world. Who would’ve thought it?

In fact, a lawsuit was even filed against the chain after a number of sandwiches measured up short in 2013. However, it was concluded natural variability in baking means it's inevitable subs will be slightly different sizes and no customer is actually missing out on food.

Every time Chick-fil-A opens a new store, the first 100 people to buy a meal receive free food for a year. Keen customers are known to wait in the car park overnight, known as the First 100 Campout, so you better arrive early.

Diner chain IHOP is renowned for its pancakes, but did you know it adds the batter to its omelettes too? It's what makes the breakfast classic extra fluffy and sweet.

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People all over the world can't get enough of KFC, and in Japan it's even a staple on Christmas Day. Thanks to a very successful ad campaign that ran half a century ago, it's a finger-lickin' festive tradition for many Japanese people to this day.

This off-menu item at Chipotle is made by preparing a burrito with a cheesy quesadilla instead of a plain tortilla. But beware, due to its popularity you’ll be charged an extra $3.50 (£2.85) for this delicious meal.

It’s not uncommon to think Pizza Hut is named after its restaurants' roof shape. However, there's no profound reason behind its name. Founders Frank and Dan Carney went with what they could fit on the sign.

Back in 2001, Pizza Hut delivered a pizza to Russian astronaut Yuri Usachov while he was at the International Space Station. The lucky pizza reportedly hitched a ride on a Russian rocket to get there. The stunt didn’t come cheap for Pizza Hut though – it is said to have cost the company around $1 million (£784,440).

Above a KFC, across the street from the Great Sphinx and Pyramid of Giza, is this prime-location Pizza Hut. Why battle the crowds and the heat when you can sit back in an air-conditioned dining room with a pepperoni pizza, soda and an unobstructed view of an ancient wonder.

Everyone loves Ben & Jerry’s ice cream because of the huge chunks of sweet treats like marshmallow, brownie and chocolate. Beyond an intense sugar rush, there’s a more thoughtful reason why they’re in there. One of the Ben & Jerry's founders, Ben Cohen, suffers from anosmia (loss of smell) so texture is very important to him.

The innovative duo had even decided a name for the business – UBS, meaning United Bagel Service. Then they found out how expensive bagels were to make and bought an ice cream machine instead. We’re happier for it, otherwise we wouldn’t have Phish Food and Cookie Dough.

The convenient restaurant chain, open 24 hours a day and 365 days a year, is an official meeting place for people using the Roadie delivery app. App users agree to pick up and drop off other people's packages on a journey they're making anyway and it’s quicker than UPS or FedEx. Eating waffles beats standing in the queue at the post office any day.

It might be called Waffle House after the sweet and golden breakfast dish but the American chain is actually one of the world’s largest purveyors of T-bone steaks. It sells them at a rate of four per minute.

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If you love Nando's but aren’t a fan of the spice, there’s another flavour option available to UK customers that isn't on the menu: barbecue sauce. It’s called Peri-Tamer and is used on kids' meals. It’s not advertised but is extremely popular, so don’t be afraid to ask.

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McDonald’s Chicken McNuggets come in four different shapes and they all have names: the boot, the ball, the bone and the bell. See how many you can spot next time you pick up a box.

Back in the late 1980s to the late 1990s, McDonald’s introduced pizza to menus at select stores in the USA. It came with toppings such as cheese, pepperoni, green pepper and onion, but was eventually phased out due to issues such as slow cooking times. Don’t you wish you could order one now?

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Crazy, right? But with McDonald's typically receiving 68 million visitors a day and nearly 15% wanting Happy Meals, all of those toys add up. The chain is the largest distributor of toys in the world.

A classic McDonald’s menu choice in the Philippines is Chicken McDo with McSpaghetti. The order consists of one piece of crispy chicken served with spaghetti in a minced beef and tomato sauce, topped with cheese. We wouldn’t say no to it.

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In the days before Ronald McDonald was on the scene, the McDonald's mascot was a miniature animated chef named Speedee. He appeared on restaurants’ signs in the 1950s, before being replaced by the golden arches.

Although you’re unlikely to spot her eating a Big Mac, the Queen of England owns a McDonald’s restaurant at the Banbury Gateway Shopping Park, 80 miles (129km) northwest of London. It's part of The Crown Estate, the monarch’s land and property portfolio, which includes Ascot Racecourse and London’s Regent Street.

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If you want a Whopper in Australia, you're heading to Hungry Jack's not Burger King. It's the Australian franchise of the brand and has all the same menu items you know and love.

Yes, it is totally possible to order a combination of fries and onion rings at Burger King. The dream menu item, also known as Frings, is available on the secret menu at any branch that sells the sides separately, so you don’t have to decide between them.

The capital of Finland is known for its saunas and one Burger King branch even has its own in-restaurant spa. Here you can usually be served regular burgers, drinks and alcoholic beverages while sweating it out in the 15-person facility. We'll leave you to decide whether it'll be a pleasant experience or not.

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Domino’s customers who live in Whangaparaoa, New Zealand, a town 20 miles (32km) north of Auckland, can have pizzas delivered by air. The drones will deliver within roughly a mile (1.5km) of the store and can travel 18 miles per hour (30kmph). This is the only location to offer the futuristic service and customers must have a big enough garden for safe landing.