At 7 p.m. on Saturday, Oct. 24, the gates at Fort Mifflin will close for the night. The people still inside will have until 6 the next morning to explore the historic site, investigate reports tied to its buildings and legends, and decide whether getting any sleep is worth the attempt.

Sleep with the Ghosts is an overnight paranormal investigation for adults 18 and older. The event runs for 11 hours, with access to heated and unheated buildings, outdoor areas and parts of Fort Mifflin that are not normally open to the general public.

Seasoned investigators from G.Host Official will be on hand during the night to help guide participants. The group will also gather around a fire pit to compare evidence and learn more about the history, myths and legends tied to the fort. And unlike a typical ghost tour, this one does not end before bedtime.

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Participants can sleep in dormitory-style quarters or bring their own tent. Fort Mifflin notes that sleeping is optional, so anyone determined to keep investigating can stay at it until the event wraps up at 6 a.m. Sunday.

The overnight event is geared toward experienced paranormal investigators. Fort Mifflin recommends its separate Open Investigation Evening for people who are newer to paranormal investigating.

Tickets cost $99 per person, plus fees.

Once the gates are locked for the night, late arrivals will not be accommodated. Fort Mifflin says tickets are extremely limited and will sell out.

Date: Saturday, Oct. 24-Sunday, Oct. 25
Time: 7 p.m.-6 a.m.
Location: Fort Mifflin, Philadelphia
Tickets: $99 per person, plus fees
Age: 18 and older
Investigators: G.Host Official will be on hand to help guide participants
Sleeping: Dormitory-style quarters or bring your own tent; sleeping is optional
Availability: Extremely limited; Fort Mifflin says the event will sell out

Have an event coming up? Let the PhillyVoice Events team know about it by emailing events@phillyvoice.com.