Hit television show, Downton Abbey has been using Lincoln Castle's male prison as a stand-in set for York Prison and this weekend visitors get the chance to see the building for themselves.
The prison isn't usually open to the public but will be opened up for Lincoln's heritage weekend, 1,000 Years of Traditional Crafts on 29 and 30 September.
Refurbishments are due to be made as part of the £19.9 million Lincoln Castle Revealed project.
The project will see the creation of a purpose-built Magna Carta centre and free entry to the castle grounds and should be completed by 2015.
Visitors will also get a chance to look round the new Heritage Skills Centre, the first new building in the castle grounds for 150 years.
More than 50 heritage skills will also be showcased, including blacksmithing, stone masonry and stained glass.
There will be lots of hands-on activities to keep people entertained, including a special marquee just for younger visitors, who’ll be able to try making a medieval musical instrument, traditional beeswax candle dipping and much more.
Also making a welcome return will be the Taste of Lincolnshire Food Fair, with delicious county food on offer in Castle Square and throughout the castle grounds, as well as cookery demonstrations in Castle Hill car park.
The event will be spread across Lincoln Castle and The Museum of Lincolnshire Life.
Lincoln Castle is open from 10am to 6pm each day, with last entry at 5.15pm.
The Museum of Lincolnshire Life is open from 10am to 5pm each day, with last admission at 4.30pm.
Admission costs £9 for adults, £8 concessions, £6 for children and is free for under five's with tickets sold at the Visitor Information Centre in Castle Square.