Oxburgh Priest Hole. Courtesy National Trust
To commemorate the centenary of lavatory legend Thomas Crapper, the National Trust is encouraging you to explore toilets through time that can be found in their properties.
As you sniff out some of these rarities it is worth bearing in mind that some regal rears have graced the thrones at National Trust properties, including the Queen Mother (at Anglesey Abbey), King Henry VII (Oxburgh Hall) and HRH Prince Charles at the aptly-named Horsey Windpump.
Oxburgh Hall is home to one of the Trust's earliest toilets, a garderobe, which is a small room that jutted out from the edge of the building doubling up as a toilet and robe store - the foul smells kept the moths away.
Blickling Hall Commode with lid up. Courtesy National Trust
The garderobe at Oxburgh Hall was used by Henry VII in 1487 and now houses the secret hatch to the priest hole which would have been used to hide Catholic recusants during times of religious persecution.
Tudors were not a very discriminating bunch when it came to what they charmingly called "plucking a rose" and wouldn't bat an eyelid about going in chimneys, corners of a room or in the street.
Queen Elizabeth I raised the standard and had a "john", the first flushing toilet invented by John Harrington, installed in her palace.
(Above) Felbrigg Hall Outdoor Privy. Courtesy National Trust
Chamber pots were the most common form of receptacle for relieving yourself well into the 1800s.
The most common place to find a chamber pot in a house in the 1700s was in the sideboard in the dining room – surely enough to take the edge off any dinner party. But what would you do if you got cut short in the middle of the night and the dining room was a bit of a hike?
The answer lies in the Chinese bedroom at Blickling Hall, where there are a pair of his and hers enclosed washstands next to the bed. Guests would pull out a drawer and find a metal pee bowl which would be emptied by the maid in the morning – one pot still remains and can be seen during Open Cupboards week.
Lord Fairhaven's en suite with unique wicker lid at Anglesey Abbey. Courtesy National Trust
It wasn't until 1775 that Alexander Cummings invented the first modern flushing toilet, but this made little impact on the majority of British families, who had to put up with sharing outside privies and poor sanitary conditions that caused many health problems.
A further luxurious lav at Anglesey Abbey. Courtesy National Trust
The toilet that we all know and love - of the closed water tank and bowl variety - wasn't introduced until 1910. Ickworth House has two original 1910 toilets which will be back on display as part of the Real Lives exhibition.
For a truly luxurious lavatory experience, have a look at the rather unusual wicker cover for a seat in Lord Fairhaven's en suite at Anglesey Abbey. There is also an elaborately decorated room with a marble floor, paintings, statues, two urinals and three hand basins.
It seems that from the Middle Ages to the 1950s, there is an opportunity to flush out some interesting secrets at the National Trust when properties open at the end of February - earlier than they ever have before.