Halloween is fast approaching and with it an increased appetite for all things spooky and paranormal. Have you ever done a ghost tour on your travels? You might turn your nose up and say it's all a charade, but ghost tours can be a great way to learn more about the history of a place, as well as upping your adrenaline levels by a notch or two. So what's there to lose? Here are our picks of three of the world's best ghost tours.

Mary King's Close and the South Bridge Vaults: Edinburgh, Scotland
Mary King's Close and the South Bridge Vaults form part of Edinburgh's historic underworld (both lie hidden beneath the Royal Mile). As you descend into the darkness and mystery of the underground closes and vaults your imagination will get a real work out as you listen to the stories of ghosts, murders, plague victims and witches.

Mary King's Close today is the remains of a mediaeval street buried underneath Edinburgh's City Chambers and the Royal Mile - the paranormal happenings that have taken place there are world renowned. When the Black Death hit Edinburgh in 1645 there were around 500 of the city's poorest people living and working in Mary King's Close; about half of them were dead or dying from the disease. The story goes that the city decided to act against further outbreak and the Close's inhabitants were quarantined in their homes and left to die. If you go down to the Close look out for a young ghost called Annie; she's been spotted by lots of people over the years and there's one room in particular that she is rumoured to haunt.

The South Bridge Vaults were built in late 18th century, and abandoned by the 1830s - the corridors and chambers are still unchanged. Burke and Hare, the body snatchers who sold corpses to medical schools, are rumoured to have hunted for victims in these Vaults.

According to The Edinburgh Ghost Project 2001 there abnormally high levels of paranormal activity in Edinburgh's Underground Vaults. As added testament to the ghostly goings on in Edinburgh's underworld, the "Most Haunted" TV team has staged one of its live shows in the South Bridge Vaults and Mary King's Close.

For more info about the Mary King's Close tour visit Mercat Tours. For more info about the Vaults tour visit Auld Reekie Tours.

French Quarter: New Orleans, USA
The French Quarter is the oldest and most famous neighbourhood in America's "Most Haunted" city. Here ghost stories and paranormal sightings mingle with the very real, and very macabre "City of the Dead": St. Louis Cemetery No. 1, where you can visit the Queen of New Orleans Voodoo, Marie Laveau.

Laveau's former home at 1020 St. Ann Street is said to be one of the French Quarter's most haunted spots. People are said to have seen her spirit, along with those of her followers, engaged in Voodoo ceremonies there.

Another must-see spot for ghost-busters is Madame LaLaurie's house at 1140 Royal Street. She was responsible for the torture, mistreatment and death of many of her slaves, and apparently you can still here the screams of her victims today.

Visitors to New Orleans can take their pick from several ghost tours of the French Quarter, amongst the best operators are Haunted History Tours, New Orleans Ghost Tour, and Historic New Orleans Walking Tours.

Read more about New Orleans' most haunted destinations here.

Catacombs of Paris: Paris, France
The Catacombs of Paris (L'Ossuaire Municipal) houses a vast collection of human bones in a network of subterranean tunnels and caverns. The catacombs were created in the 1780s to house remains overspilling from the city's overcrowded and badly maintained cemeteries - it's thought that there are around six million Parisians buried in the catacombs.

Believers maintain that the way the bones were uprooted from their original resting spots and placed in the tunnels was disrespectful and this is what causes the paranormal hoo-hah in the catacombs. There have been reports of ghostly voices and moving shadows down in the underground tunnels. Are you brave enough to handle it...?

Find out more about the Catacombs Ghost Tour here.

Have you been on a ghost tour? Which one did you take and what did you think?

Photo Credits: "Ghost Tour" by thecnote; "Haunted? 1140 Royal Street" by raelb; "Catacombs" by jrmyst. All via Flickr (Creative Commons).