Every town had a traditional one which had been there for years, but they are dwindling away now, replaced by fly-by-night sandwich joints, staffed by untrained students just serving for a job - a temporary job. The Italians and French still take it seriously, though, with middle-aged waiters - white cloths hanging from the front of long aprons above white shirts and black trousers.
I remember watching just such a waiter taking a cigarette break outside a traditional place in St Marco, Venice - great plumes of smoke issuing from his mouth as he stared hard at the rival establishments across the square. He smoked as if he were just about to be executed, and threw the half-finished thing into the gutter with absolute hatred when a shout from inside called him back to work.
The staff in classic, British tea-rooms were all elderly, belligerent women who made it clear that you entered their establishment on sufferance, and any items listed on the menus could not - under any circumstances - be rearranged by omission or addition into something which was not precisely prescribed by the wording. "I'll have a round of cucumber sandwiches, please. Oh, and hold the cucumber." Oh no you won't, young man, but you may have two slices of bread and butter.
I used to prove to my friends in the early 70s that I was not a hippy by entering any of these tea-rooms in Glastonbury which, at the time, all had a hand-written sign outside saying 'No Hippies'. Despite having shoulder-length hair and tatty jeans - just like my friends' - I was usually the only one allowed in to be politely served as a respectable citizen. I guess they were just as happy with my self-image as I was at the time.
Dublin has Bewley's Oriental Cafe - a massive, Egyptianesque establishment (since 1917) on about 4 floors, with a restaurant above and a basic caff in the basement. A wonderful place.
Cambridge (where I briefly lived in the 70s) had 'The Whim' - now sadly gone after many years. I used to go to The Whim every afternoon, and I befriended a handful of Dons because one of them (a gay one) thought I looked decorative, and asked me over to their table. Yes, I did look quite decorative in those days, believe it or not. They had the most indolent lifestyle of any professionals I have ever met. Lunch at a pub, tea at the Whim until about 5.00 p.m., then along the road to 'Shades' wine bar, where they would drink until midnight, then the whole thing all over again the next day.
I later learnt that the gay don was a key figure in the Anthony Blunt spy saga, though I had no idea at the time. Sometimes I miss the Cold War. I think a lot of Russians do too.
When staying in Hamburg once, I found what looked like a classic, English tea-room run by elderly women serving very basic food, and I used this place for breakfast every morning for weeks. There would always be three or four very large, middle-aged men sitting there, who got to know me and bid me 'good morning' as I entered.
Eventually, my German friends asked me where I went every morning, and I told them. They looked at me in horror, and told me that this was an exclusively gangster cafe for the mob on one side of the ReeperBahn. Apparently, the week before I arrived, one of the thugs from the other side of the street went into the cafe, shot one of his rivals through the head with a pistol in full view of the old ladies, then went back across the road to his own cafe. They must have recognised that I was a mere civilian.
In the 1950s and 60s, cafes existed where you were led to a table which had a massive tazza in it's centre, piled high with buns, cream cakes and iced fancies, and you simply helped yourself from it (under strict supervision from your parents). The waitress then counted how many buns were missing before writing out the bill, totting the damage up accordingly.
Cup cakes had not made it over the Atlantic at that time, although there were some truly horrid chocolate things going by that name, sold in boxes and individually wrapped in (poured into) pleated foil cups which tore away from the dark sponge with a muffled, machine-like ripping sound. More of a feel than a sound, actually. Anyone old enough to remember them?