Inspector Morse (et al) come to mind as one that lasts longer. So many great British detective shows that go on for decades, with around 20 movie-length episodes per season (aka series).
Is that a typo? Inspector Morse had a total of 33 episodes across 7 seasons and 5 specials. Seasons averaged about 4 eps each.
https://en.wikipedia.org/wiki/List_of_Inspector_Morse_episod...
The Bill may have more episodes, but Doctor Who has been running for 20 years longer.
The prototypical "long lasting UK series" is actually https://en.wikipedia.org/wiki/Coronation_Street (nearly 60 years, >10000 episodes)