1. Literally every National Park.

Out of all the tourist attractions I've visited, I've absolutely never been disappointed by a National Park. While it doesn't necessarily offer the thrill or even ample bathroom stops, National Parks offer a glimpse at the true scale of the world and I often find myself awed by the scenery and history contained within National Parks.

2. Stonehenge.

Ten-foot-tall slabs of stone mixed with one of history's greatest mysteries make this an attraction that is a shame to miss. While it is smaller than you think, Stonehenge is still a sight. Despite the crowd, it's not hard to get a decent picture or see the stones closely. And sometimes on the summer solstice, visitors are allowed to step right up along the stones. This often draws thousands of people though, so you may be better off just coming on a normal day and seeing the stones from a short distance.

3. Pike Place Market.

Farmer's markets and marketplaces are a common attraction in cities all over the world. However, Pike Place Market, in Seattle, Washington, is one of the most famous. Between the fish throwing, hole-in-the-wall bookstores, and endless smells of baked goods, Pike Place is a tourist attraction worth just taking a stroll through and absorbing its long history.

4. Edinburgh Castle.

If you visit Edinburgh (which I highly recommend), it's impossible to miss the sight of the Edinburgh Castle that sits on a hill above the city. However, if you venture down the Royal Mile, you'll eventually end (or begin) at Edinburgh Castle. Inside you can see centuries-old architecture, records of Scottish veterans, and the Scottish Crown Jewels. Not only is the castle a work of it itself, but its history is also one that any of the emphatic tour guides will tell you is a great one.

5. The Smithsonian.

The Smithsonian is a must-see for anyone, regardless of your own interest in history. The Smithsonian contains priceless artifacts of United States history, as well as world history. From art to women in WWI to natural history, the Smithsonian has collections and exhibits that interest everyone. While crowded, the museum is worth it to see history first hand.

6. Powell's City of Books.

Powell's City of Books in downtown Portland, Oregon is a stop for tourists and locals alike (although locals may be more likely to visit one of the locations not located downtown). The bookstore is famous for taking up an entire city block and for being the largest new and used bookstore in the world. For bookworms, this is a must stop. And, even for those not inclined towards books, you're likely to find something that interests you among the nearly one million books.

7. Hoover Dam.

Straddling the part of the border between Nevada and Arizona, the Hoover Dam is a reminder of the Great Depression and an era of great growth, but also of great despair. Between the dam's history and the science behind hydroelectricity, the Hoover Dam is an interesting way to spend a couple hours. Located not far from Las Vegas, this is the perfect tourist attraction to get you out of the city, but also learn something along the way.

8. Griffith Park.

Griffith Park contains many tourist attractions in one; including the Griffith Observatory, Los Angeles Zoo, and views of Los Angeles, and Hollywood Sign. Griffith Park also provides hiking in the middle of one of the largest metropolitan areas in the US. It's a place that will tick many things off your to-do list in Los Angeles and the perfect place to get lost and discover.

9. San Diego Zoo.

San Diego has a reputation of being one of the best zoos in the US and it certainly doesn't disappoint. The zoo is huge and takes nearly a whole day to experience it fully. However, with many animals species you likely haven't seen before, as well as many crowd favorites, you'll want to stay the whole day anyway.

10. The Royal Mile.

The Royal Mile in Edinburgh, Scotland, stretches between Edinburgh Castle to Holyrood Palace. Along the mile are various quirky restaurants, museums (all of which are free), and shops. Explore the closes, take the Ghost Tour to learn a bit about Edinburgh and Scottish history, and enjoy strolling down a road that seems to transport you back in time. While the Mile does tend to be crowded from time to time, it is not nearly as crowded as Princes Street and much more worth it.

11. Buckingham Palace.

Probably one of the most famous residences in the world, Buckingham Palace is also one of the most popular attractions in London. The Palace, while crowded, is easy to snap a pic of and even if you don't take the tour is a short walk from other attractions. You don't have to go out of your way to visit or pay an abhorrent amount of cash. One of the coolest attractions is the changing of the guard, which happens at certain times each day. It's free to watch and honestly a pretty cool experience. You can take tours of Buckingham Palace, but that will cost money. If all you're wanting is a quick selfie, this is an easy place to do it.

12. Your backyard.

OK, so maybe not your backyard specifically, but we often tend to gloss over the attractions within or near our own cities/ communities. While sometimes this may be a wise decision, other times you may be missing out on something truly worth seeing. So, get out there and explore, because you never know what you're missing.