That was the last clue I filled in, with all the crossers in! I got it from Brendan’s hint, and after much googling. I really get stumped by clues that refer to British peculiar names or news, like the rivers or islands names, like in 20d. Most other proper names also, like in 17d, 16d and 14a, I had to google, though they were bit easier cf. 19d. Yes, it was a bit difficult puzzle today with so many proper names.