100 year old houses are relatively new by UK standards. A large proportion of the urban housing stock is Victorian terraces (i.e. pre-1900). Rural houses are usually older. The suburbs/urban sprawl are the main exceptions. [1]

Partly this is because we don't build enough new houses, but it does mean there are lots of lovely old buildings. My house is 250 years old. It's nothing remarkable. Next door is about twice that age.

[1] https://maps.cdrc.ac.uk/#/metrics/dwellingage/