Norwich — On Franklin Street, hidden amid tired old houses converted into apartments, laundromats and mom-and-pop stores, there’s a basement firing range in a long-shuttered factory, a paved lot where defective guns are said to have been buried, and remnants of an underground stream that once turned turbines for a long-gone city industry.These were among highlights described during a two-hour urban hike Monday that took about 40 people to locations significant to the firearms factories that once thrived here. Leading the walk were members of a group dedicated to making the city’s former prominence in firearms manufacturing as well known a part of the city’s history as its textile industry.

“Norwich was once considered the firearms center of New England, from the Civil War to the Great Depression,” said Ed Tollmann, one of three members of The Guns of Norwich Historical Society who led the walking tour. “It has been said that in 1860, more firearms were made in Norwich during the Civil War than any other city in the country.”

Tollmann, joined by fellow group member Burton Jernstrom and David Oat, the group’s president, told the story of the city’s firearms industry through the personalities behind it. There were entrepreneurs like Charles Converse and inventor Christopher Brand, who secured a patent on a whaling gun that replaced the harpoon, and gunsmiths like Alvah Grimes and Horace Smith, who ultimately joined with Daniel Wesson to form one of the nation’s most famous gun manufacturers.

“A lot of people don’t know that Smith & Wesson was a Norwich company,” Jernstrom said.

The company, he explained, began in the city in the 1850s manufacturing pistols and ammunition before eventually moving to New Haven.

Over the seven decades the firearms industry existed in Norwich, 20 different factories turned out various types of rifles, pistols and revolvers sold to individuals as well as to the federal government to supply Union troops in the Civil War. During World War I, the Hopkins & Allen Manufacturing Co., the largest of the companies, made rifles for the Belgian government in exile, employing some 600 workers in the vacant brick factory on Franklin Street with the basement firing range. The factory, built just before the war, was actually the company’s second in the city, a replacement for one that burned to the ground in 1900.

“It must have been an unbelievable fire,” Tollmann said, holding a laminated copy of a photo of the huge pile of rubble left in the fire’s aftermath. “This whole block was gone. But it just amazes me how these people just kept going.”

Norwich gun makers developed many innovative and unique designs over the years, though not all were successful. A breech-loading shotgun patented by Osgood Gun Works offered the unusual feature of being able shoot both .22-caliber and .32-caliber bullets, but had a design flaw that proved injurious to its owners.

“There were a lot of people who lost a couple of fingers,” said Jernstrom, holding a drawing of the Osgood duplex single action revolver.

Tollmann said the group has been leading the walks annually for the past nine years, at first as an independent event. In recent years, the walk has been incorporated into the annual Walktober series organized each October by The Last Green Valley, the nonprofit group that promotes preservation and appreciation for the assets of the 35-town region of the Shetucket and Quinebaug rivers.

As the walk concluded, Tollmann invited others to join their group, which meets bimonthly at the Yantic firehouse, and to share any information and artifacts they may have to help fill in gaps in the story of the city’s gun industry.

“As you can tell,” Tollmann said, as the group gathered at a parking lot where the Ryan revolver factory once stood, “we’re kind of into this whole thing, so we get a little long-winded.”

j.benson@theday.com