The historic Clandon Park House has been left a "shell" after a devastating fire destroyed most of the 18th Century stately home, the National Trust said on 30 April.
The intense blaze at the Grade 1-listed building began in the basement on 29 April at 4pm GMT, and quickly spread throughout the house, collapsing the roof, ceilings and floors.
Some 80 fire fighters from 16 crews tackled the huge blaze at the stately home, near Guildford in Surrey.
"The fire is now out but the scale of the damage to the mansion has been devastating. The house is now essentially a shell, most of the roof, ceiling and floors have collapsed into the bottom of the building," Dame Helen Ghosh, the National Trust's Director General, said on Thursday.
"There is perhaps one room that is relatively untouched but, other than that, the interior is extensively damaged. The external walls are still standing. It's a terrible sight. We have saved some significant items, but certainly not everything that we wanted to save."
Many valuable historical artefacts, including a prized collection of 18th Century furniture, porcelain and textiles were saved from the blaze, but the interior of the building suffered catastrophic smoke and fire damage.
There were no reports of injuries, and an investigation has began into the cause of the fire.
According to the National Trust, Clandon Park was built by a Venetian architect for Lord Onslow in the 1720s and is one of the most complete Palladian Mansions in the country.
The house was donated to the Trust in 1956 and was used as a venue for weddings and corporate functions.