More than 50 firefighters are tackling a “serious blaze” at the historic Wythenshawe Hall in Manchester.
The blaze started in the roof of the Tudor building at about 03:30 GMT, Greater Manchester Fire and Rescue Service (GMFRS) said.
Ten fire engines and an appliance “similar to a cherry picker” are at the scene.
The timber-framed hall was built in 1540 and was home to the Tatton family for about 400 years.
No-one is thought to have been hurt but the building has been damaged.
Warren Pickstone, from GMFRS, said: “We are doing everything we can to save as much of this building as we can.
“The fire is in the roof and is difficult to access but we have specialist resources at the scene and we are doing our best.
“The fire is in the main black and white traditionally clad Tudor building with the historic clock tower, which was also on fire. So far we believe we have lost the roof and the first floor.”
The hall was donated to local people in 1930 and was previously run as a museum and art gallery.
Wythenshawe Hall was formerly owned by Manchester City Council but is now run by a Friends Group.