The remains of a bath-house built by the Romans during their conquest of the north of England has been recognised as a national monument.
Archaeologists discovered the structure of the building after excavation work was carried out on the site in 1978.
The bath-house was used by soldiers to relax, socialise, play games and keep healthy.
Its remains are preserved beneath a grassed area at the junction of Church Street and Savile Road, Castleford.
The site has been named as a national monument, following approval by the 1979 Archaeological Monument Agricultural Area Group.
It means the area is protected from developers and it has been recognised alongside 19,000 other monuments, including Hadrian’s Wall.
Castleford Heritage Trust chairwoman Alison Drake said: “We are really pleased because this is something we have wanted for a long time.
“This puts Castleford on the map as the site will be named alongside other monuments around the country.
“The Romans coming here is a very important part of the town’s history and it will help make it a destination.”
Neil Redfern, Historic England’s principal inspector of ancient monuments for Yorkshire, said: “The area met the characteristics of something which should be protected.
“The Romans strategically based themselves by the River Aire and from there headed towards York. Castleford played a big part in the Roman’s conquest across the North.”
The Heritage Trust erected a plaque on the site to acknowledge the bath-house.
Mrs Drake said: “We set up the trust to originally put a museum on the site. There are no plans at the moment to explore the area because if we did that then we would need to build a structure over it. The Heritage Lottery Fund maybe more inclined to give us some money should we decide to do something.”