For the last ten days, visitors have been able to watch archaeologists at Attingham Park expand a site first discovered in 2018.
Remains of an elaborate, neoclassical style summerhouse were first discovered four years ago, during work to create new service routes. Later, in 2021, an ornamental pool was unearthed.
Over the course of the most recent dig, staff and volunteers have discovered a second building, around double the size of the summerhouse, and a curving boundary wall.
The discoveries indicate the site was a former, private pleasure ground built in the early 1800s, and left abandoned by the middle of the century.
Nigel Baker, a local freelance archaeologist, said: "What's truly extraordinary about this place is that an entire park within a park, a secret garden, was lost. It would've been an incredibly lovely place for the few years it was around."
Archaeologists say the evidence uncovered is pointing toward the structure being built for use as a servants building.
"We know that this was built in the time of the 2nd Lord Berwick, who is famous for the amount of money that he spent," added Nigel: "it's unlikely that he was the type of man who would make his own cup of tea, or put his own log on the fire.
"It was no surprise to find the pool aside the summer house but the missing factor was the servants. We think this is the building that accompanied them."
Viviana Caroli, National Trust Archaeologist, said the find was an exciting opportunity to tell the story of the beating heart of the Country Estate.
"We have so few historical documents about this site, so what's really exciting is that if this building is a service building, we can tell the stories of 'normal', working people.
"It shifts the attention towards all the people that made this possible, telling the hidden stories. That would be a nice story to tell."
The team hope to return to the estate next year, to expand the excavations to the West.
The site will remain open for visitors to explore for the next few weeks, within the grounds of Attingham Park.