Soldier Museum, Houghton Hall PE31 6TY
https://www.houghtonhall.com/visitor-information/disabled-access/ "The Stables Café, Soldier Museum, & The Gift Shop:
The whole stable block is accessible for wheelchairs/pushchairs, although the stable yard is covered with cobbles. There is a disabled WC in the stable block and nappy changing facilities for babies."
Always check with the venue directly for up-to-date information including opening times and admission charges as they may be subject to change