I've been to quite a few over the years, not all pop - mostly here in London but saw Sting, Gloria Estefan and U2 ( don't like them except for my theme song "still haven't found what I'm looking for!) in Cape Town as well as local musicians like Louis Mhlanga and Vusi Mahlasela.
Van Morrison (he was in a bad mood), Keith Jarrett in San Sebastián, near where we used to live (ipad did that accent, not me!)
London: Oscar Peterson
Alison Krauss and Union Station
Ali Farka Toure
David Gray
Prince (top deck of the O2 so couldn't see or hear)
Bob Dylan ( cheaper seats at wembley arena so as Prince

)
Jan Gabarek & the Hilliard Ensemble in St Paul's Cathedral
Shakira (!)
Santana
James Taylor
Zakir Hussain
Walked out of some Canadian wailer at the Barbican, along with many others. Have forgotten her name, if not her out of tune voice!
Going to see the Boss in June
Would really love to have gone to see REM and would paddle a canoe across the Atlantic to see JJ Cale.
I mostly go to concerts I can get to, so north or west London don't feature and they often get the best concerts.
Years ago when young and healthy I went to Womad, when it was in Bracknell. I've never forgotten Nusrat Fateh Ali Khan. I went into a sort of trance, which embarrassed OH so he jabbed me in the ribs to snap me out of it!!