CHICAGO (CBS) — It’s been said that Chicago is one of America’s most haunted cities.

Chicago’s early settlers and gangsters reportedly still linger at historic hotels, restaurants, monuments and back alleys.

“Chicago is the city that was baptized in blood going back to the time of the Fort Dearborn massacre,” said David Cowan, co-owner, Chicago Hauntings Ghost Tour.

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Cowan, along with his ex wife, renowned author and ghost hunter Ursula Bielski, share the Windy City’s legends and lore with thousands each year.

“Chicago in itself has a very fascinating history. We think we do a very historically based, sophisticated tour that is aimed toward the more mature audience.”

On a crisp, dark October night, his buses are packed with patrons who are looking for a history lesson and some good ghost stories.

Allison Nettles from Frankfort brought her whole family on the tour.

“I’m totally a believer that’s why we’re here. It’s just something we’ve always been interested in,” Nettles said.

Tonight, a spooky tale of the Excalibur nightclub, Holy Name Cathedral and Chicago’s own Lincoln Park which used to be the city cemetery, 18,000 bodies still buried below.

Ghosts from Chicago’s St. Valentine’s Day Massacre of 1929 also haunt Clark Street.

“This is a very, very haunted site,” Cowan said. “Very interesting indeed. Very intriguing. One of my favorite spots and one of Chicago’s most infamous scenes that remains unmarked. It’s a parking lot next to an assisted living home”

The tours follow a course of history that starts with the very beginnings of Chicago, traveling from its origins as a frontier outpost, through the 19th century — including the Great Chicago Fire and its aftermath–, into the 20th century and the gangster era of the 1920s and 1930s, and forward to today.
Cowan says every tour is different.

“We do a special Archer Avenue Resurrection Mary tour, a ghost and gangster tour, a Chicago Fire tour,” Cowan said.

The tours are based on Bielski’s nearly 20 years of Chicago ghost hunting and her “Chicago Haunts” series of books, as well as the collective writings and ongoing research and investigations of the entire Chicago Hauntings ghost hunting team.

For patrons, most walk away with a new understanding of Chicago and plenty of spooky stories to share.

“We run year round but this is our busy time,” Cowan said. “It’s a good season to do it.”

For more information on the tours or make a reservation log on to chicagohauntings.com