It wouldn't be Halloween without ghost stories. Or better yet, ghost sign stories.

What is a ghost sign? It's any old painted advertisement on the side of a building, usually spelling out the name of a company + a description of their goods or services.

Given Boston's industrial history, ghost signs are everywhere. Here’s what we know about three of these signs and where to find them.

👻 Bostonia Cigars

When walking around the Rose Kennedy Greenway + Haymarket area, you've probably recognized this 10 cent cigar advertisement. If you haven't yet, head to Blackstone Street to see the sign dating back to the 1880s.

Pro tip: While you're there, keep an eye out for the sign of a hand pointing down on Marshall Street.

👻 NECCO

This one is a bit harder to notice, but there are still lingering letters from a New England Confectionery Company Factory space at Necco Court in the Seaport District.

The candy company also has a historic factory complex at 250 Massachusetts Ave. in Cambridge, which is now owned by Novartis.

👻 Holt & Bugbee Co.

You'll find this sign from a locally founded hardware flooring company on 90 Canal St. in the North End. Fun fact: The business, which operated in Charlestown for 60 years, is still around in Tewskbury.

Honorable mentions go to the Quaker Oats signs in both Cambridge + the South End, and the Coca Cola logo on Colombus Avenue in the South End.

If you're curious to learn more, check out The Backside of America. Newton local Dave Brigham regularly explores our city and documents all of the ghost signs he finds on the blog. Naturally, we're big fans.