Not all tours must be done via public transportation, and walking tours can very much be about getting a 'local' feel for a travel destination. For some, we don't need to look very far; walking tours exist all over the world. Part of the fun of a walking tour is being able to experience everything outside of a mode of public transportation. However, some are definitely stranger than others.

There are picturesque walking tours which offer plenty of photo ops and a lengthy history, while others are a bit more on the morbid side. We're talking catacombs, the site of a notorious serial killer, and even a trip through the Big Apple's most grimy of locations. These things do exist and for the daring, they can be totally worth the pedometer points.

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10 The Paris Catacombs AKA 'The Empire Of Death'

You're seeing correctly. Wall-to-wall skulls and bones line the corridors of the underground catacombs in Paris, a tour that definitely provides a unique experience. Simply put, these catacombs were used in the latter half of the 1700s to house excess bodies, since cemeteries were becoming overrun. While it's a gruesome thought, if the dead could talk, we have no doubt that they'd divulge some secrets down here. The catacombs hold historical significance as well as an interesting walking tour for the more morbid of humans. They also offer 'dark tours' which are not for the faint of heart.

9 The Breaking Bad Tour

It's a little unusual—then again, aren't all the good tours?—but it's pretty popular: The Breaking Bad walking tour. The show had to be based on something realistic, right? While the harrowing events that took place in this award-winning show are fiction, the locations they're based on are not. Those who choose to go on this tour will have the opportunity to see all of the real-life businesses and locations, including Walt's house as well as Jesse and Jane's apartments, that the show was based on. It's really a dream come true for hardcore Breaking Bad fans.

8 Amsterdam's Red Light District Tour

For those who are a bit more progressive in nature and don't mind a little spice in their life, we present you with the Amsterdam Red Light District walking tour. We don't think much needs to be said about what you'll encounter on a tour such as this since anyone who's familiar with Amsterdam is likely well aware of their red light district. However, these guided tours aren't just about the salacious reputation of Amsterdam—it also includes a bit of history and a guided walk led the locals, who know the area better than anyone.

7 The Charles Manson Helter Skelter Tour In L.A.

For a drastic change of pace, the Helter Skelter tour in Los Angeles is one that's not as upbeat or unusual as some others. This tour takes roughly three hours and is led by Dearly Departed tours. Tour guides educated their tourists on the murder of Sharon Tate along with all the gruesome details that many are unaware of. Tourists will view all the locations associated with the crime as they learn of Charles Manson and his cult following, as well as getting a detailed insight into the lives of all those involved. It's not everyone's idea of a worthwhile tour, but it might be of interest to those who follow true crime.

6 A City Sewer Tour In None Other Than New York City

A New York City sewer is probably the last place that anyone wants to be, but that doesn't stop Steve Duncan from conducting tours there. The tours must be booked in advance, but, for those who have a strange fascination with the inner workings of the city's plumbing, a tour such as this might just be worth it. On the tour, visitors will learn all about this history and method behind the city's drainage system. The inner workings of plumbing and sewage go far beyond the flush of a toilet and all those interested will get a lot from this book-in-advance tour.

5 The United Kingdom's Crop Circle Tour

Where are all the X-Files fans when you need them? That's right, the U.K. has guided tours that are specifically dedicated to crop circles. While not much is known about how these vast designs are formed, many have speculated that some are falsified while others seemingly have no origin. Regardless, this tour costs a whopping six-thousand and has some pretty specific restrictions for those who decide to jump on-board. The tour itself lasts nearly a week, all participants must sign a waiver, and those with pacemakers are urged to take a pass due to the unpredictable nature surrounding these sites.

4 An Undersea Walking Tour In Grand Baie

Perhaps walking around on land isn't your thing, but swimming is. No problem! The undersea walking tours offered in Mauritius will have you swimming with the fish in no time... in a good way, that is. This is a unique experience, albeit slightly strange, like no other. The tour itself lasts roughly 20 minutes and allows tourists to hang out just below the surface. It's likely that you'll see several species of fish who aren't afraid to swim right up to your underwater helmet. Fish-feeding is part of this tour as well, and there are professionals in the water with you, just in case.

3 The Rubbish Tour In London

Similar to how New York City has sewer tours, London has rubbish tours. Every city has to have something, right? On these tours, visitors will learn all about, well, garbage! Believe it or not, the city has a long history with what is now deemed 'garbage,' as tourists will learn things such as how dog feces was once used in conjunction with leather tanning. Additionally, tourists will get a solid feel for the city as you pass by various landfills and historical reference points, all having to do with the city's modern disposal system today. It sounds strange but you never know... perhaps garbage can be interesting after all.

2 A Bollywood Tour In India

Bollywood produces twice as much as Hollywood does, so it's not surprising that there's so much hype surrounding this film industry. For those who are true lovers of Bollywood, Bollywood Tourism is definitely the place to consult with. Fans will have the chance to observe all the inner workings of the film industry on an actual set, giving them a once in a lifetime experience. Additionally, depending on the type of tour you're seeking, you can add options such as film class and meeting well-known Bollywood directors.

1 VampireHaunts In The French Quarter Of Louisiana

It's not surprising to hear that something like a Vampire Tour can be taken while visiting New Orleans, as the city is famous for its folklore and legend. Even more so, the city is known for having a reputation deeply rooted in the mystical arts. Just ask anyone in the French Quarter, which is where this tour can be found. For those who want to take their vampire love a step further, New Orleans is home to the only authentic 'vampire shop' around. After learning about vampire-like crimes, nightwalkers, and vampire hangouts, take a stroll through the shop and bag some customized fangs.

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