London is one of the most popular cities on the globe for tourism. From Big Ben to the West End, it's no surprise that so many people would love to spend time in the big city. However, for tourists and travelers visiting London for the first time, there are a few common rules that no tour guide will ever really tell you once you get there.

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Because the city never sleeps, there are dozens of ways to get around town, save yourself money, and treat locals and other visitors in kind and compassionate ways while visiting the city. Here are the 10 Things We Wish We Knew Before Visiting London.

10 Bring comfortable walking shoes

Once you're in the city, one of the first things you'll notice about London is how many people are actually there! London's one of the world's biggest cities, and many people go through their lives by walking wherever they need to. Though a subway system does exist, you'll find out pretty quickly that many Londoners don't own their own cars and have no problem getting where they need to by foot.

However, to stay comfortable and energized - especially as a tourist - you're going to need walking shoes, or shoes that won't hurt your feet after walking a few miles!

9 Get an Oyster card

London is a HUGE city, and if you're only visiting for a few days, getting an Oyster Card is probably the best thing you could do for yourself on your trip. While many Londoners walk to work and walk to the grocery stores and walk back home, if you're wanting to cover all the parts of the city, you'll need to take the tube - London's underground subway system.

Your Oyster Card is your fast pass for the entire London Underground. It's FREE to get, and you'll be able to load money on it as often as you like. The tube runs through all central London and all over England. It's a necessity while traveling here!

8 Museums and art galleries are free

Unlike other big cities such as New York or Los Angeles, many of the museums and art galleries in London are completely free to get in. All you have to do is walk through the door, and you'll be just a few feet away from some of the greatest vintage, contemporary, and modern art that the world has ever seen.

From museums on World War II to classic English history museums to The Natural History Museum (a great spot for travelers with young kids), Central London has a lot to offer for those who appreciate great art and history.

7 Always have an umbrella or jacket

London is known for being a "gray city," meaning that 80% of the time, the sun is NOT shining. This isn't to say that it's always going to be rainy, but many Londoners carry with them an umbrella or jacket in the case that rain showers happen out of nowhere - which happens more likely than not.

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As a tourist - especially if you're traveling on foot - you don't want to be caught outside with no umbrella or coat to keep you dry. Even in the summer, England experiences stormy and windy weather. It's better to be safe than sorry!

6 Tipping isn't essential

Unlike most restaurants in the United States, in Europe and in London, tipping your server at a dine-in restaurant isn't required. In fact, many times it can be considered a little rude. Waiters and waitresses in England know that serving you is their job, and it's a common theme that they feel they don't need to be paid extra by their customer to acknowledge their service.

While leaving a tip may seem like a kind gesture, it's not really necessary. Whether you're ordering drinks at the local pub or even taking a cab ride, you won't really have to worry about it.

5 You never really need to take a cab

Cab rides from one end of the city to another can become super expensive, and if you're a traveler on a budget like most people, you'll find that you can save so much more money by taking the tube and using your Oyster card to pay the simple one-way fee.

Many times, even bus rides from one part of town to the other can be way cheaper than paying a taxi. Don't forget, too, that walking is also your friend in London, and you just might find yourself a little more comfortable in the big city figuring out which route to take on your own!

4 Go to a football game

Whether you're a sports fan or not, football is a HUGE part of English culture, and if you're someone who really loves to immerse themselves in the local lifestyle of the cities you visit, going to a football game is the ultimate way to do it in London.

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Even if you're not a sports fan, many stadiums have popcorn and snacks available for purchase. When you take a few friends or a few family members along, it can turn into a great night out. You'll see for yourself just how passionate the country is about their football, and you'll have a great story to tell your friends back home.

3 When on the tube, give up your seat for those who need it

This is just simple common courtesy. When riding the tube throughout the day, you'll discover quickly that there are times where a train can be more occupied than others. There aren't enough seats on the tube for everyone to always sit on and many commuters are left standing.

Something you can do to as a tourist to be respectful to the local culture around you is to give up your seat if you see someone elderly, handicapped, or with young children standing. It's a kind thing to do, and it makes for better traveling for everyone overall.

2 You can buy beautiful (and cheap) souvenirs at outdoor markets

London is a smart city, and they know that tourists from all over the world come to visit at any given time of the year. Because of this, many stores and giftshops know exactly how to charge just a little bit extra on their souvenir items. You'll find that "I Heart London" shirts can cost more than they should.

However, for a true London experience, spend a Saturday or Sunday at an outdoor market. Borough, Chelsea, Camden, and Greenwich market are great places to go. You'll find fresh food and handmade, unique gifts for low prices that would make way better souvenirs than a snowglobe with Big Ben in it.

1 Spend time walking

Again, because London is such a big city, it has a lot to offer. Take advantage of London by traveling on foot whenever and wherever you can. When you take the tube, there is so much you miss seeing because you're underground. However, if you're walking through Kensington Gardens and then suddenly find yourself in central London, it can be a fun experience.

You'll pass by many local coffee shops and mom-and-pop shops that make the city and its culture really special. London is a great place so make sure that you allow yourself to see every part of it!

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