Trust me, you wouldn't want to be a payphone in Manchester city centre. Never a minute's peace with the constant yabber, yabber, yabber and all those germy mouths and hands mauling you every hour of the day. It would be like being a waitress in an Amsterdam knocking shop. And the slamming! Why does everyone do that? Would they treat their own phones like that?

Anyway, I'm in Manchester's Piccadilly Gardens because the payphones here are apparently the most frequently used in Britain. You can tell this because there are 21 of them in this spot. Can you believe that? I didn't think there were 21 phone boxes left in the whole of Great Britain. Now that even eight-year-olds and the homeless have mobiles, who the hell uses them any more?

The first person to offer an answer is Kerry Wilson, 23, who has been talking in a call box for ten minutes. It is not yet 10am. “I was speaking to my mum,” she says. “I've locked my car keys and mobile in my car and she's bringing me the spare key.” Ah. So she doesn't normally use payphones, then? “Oh God, no. This is the first time in about two years.”

Mmm. Doesn't really solve the mystery, does it? And how come half the people have a mobile phone resting atop the counter while they talk on the payphone? “Because my mobile's run out of battery,” says Ben Atkinson, 30, looking at me as if it's the dumbest question he has ever been asked. Who was he calling? “My girlfriend.” Kathleen Smith, 45, who has also been clutching a mobile while talking on the payphone, provides another explanation. “I was calling an 0800 number,” she says. “They're not free if you use your mobile and I knew it was going to be a long call.” Quite clever. But nothing I've heard so far is going to make Mr BT very rich.

I spend many hours just sitting here, watching. It's a sunny day so there are probably more people about but I'd reckon that the payphones here are used on average once every two minutes. Maybe people are on lower incomes here. Maybe they are having more affairs. A lot of users are foreigners sending e-mails and texts. Did you know that you can do this from a call box these days? And for only 20p a go. For calls there's a minimum charge of 40p but apparently you get 20 minutes' talk time. Olakan and Jelilat, a couple who have definitely been getting their 40 pence worth, are fans of phone box thrift. “We've been calling a friend on their landline,” says Jelilat. “It is so much cheaper than phoning from your mobile. I always use phone boxes. They're good value for money.”

At last. Music to the ears of the Save Our Phone Boxes Campaign. Alan Wilkinson, 78, is waiting until after noon to call his friend in Malta. “It's much cheaper than using my home phone,” he says. Why? “Dunno, but it seems to work out at about half the price.”

But here's the thing. I notice that some people who use phone boxes look, well, suspicious. Like the suited man wearing a wedding ring who glances round furtively while conversing for nearly an hour at lunchtime. Is it because he'd prefer his wife not to see the record of the call on his mobile bill? We'll never know. “Do you mind me asking why you were using a payphone when you have a mobile in your hand?” I ask. “None of your bloody business,” he replies. Oh dear. And then there was the shiftylooking, unshaven young man who had two mobiles in his pockets and definitely didn't want to talk to me. “Just leave it, love,” he said, slamming the phone box door. Obviously a drug dealer, I thought, then felt guilty because the poor lad was probably only phoning his sick gran.

I'm getting bored now, so I chat to a nice BT engineer who has come to install anti-blocking devices on the phones. Apparently, shady types disable the phones so that when you put your money in they don't work. You assume that the phone is out of order, but when 20-odd people have done this the blocker, hovering near by, recovers all the money. “They make £50 a day,” says the engineer. “We have two people permanently on duty trying to stop the blockers.” He points to two boxes near the Arndale Centre. “See those? The most blocked phones in Britain, they are.”

So there you are. Another phone box fact for Manchester, the city single-handedly saving the payphone. You'll be grateful for that one day.

CAROL MIDGLEY

It's red, it has a very big spider living in the back left corner, it is in the pretty hamlet of Wixoe in Suffolk and its number starts 01440. BT says that it was used only once in the past year. So, until yesterday, it was the least-used telephone box in the UK.

That's right. Only until yesterday. I ruined everything. It was like one of those theoretical particles that stop existing as soon as you look at them. There was no signal. I had to make a few calls. What else could I do?

Sandra Revell, who lives next door, said that I was the first person she had ever seen inside the phone box. She has lived here for a year, so I suppose she must have missed the other person. Roy Taylor lives on the other side. “It used to be fairly busy,” he says, while raking leaves from the verge. “Lots of people passing through. It would be a shame to see it go.” Taylor has been here for 41 years, so I guess he's going back a while.

You get one village after another in this little corner of England. Ridgewell, Great Yeldham, Sible Hedingham, Gosfield. Every one has a phone box, standing proud and red. A few miles away in Stoke by Clare, and across the road from another one, shopkeeper Susan Cumber tells me that she used to use her local box quite a lot. Most people did. When she moved here 28 years ago, hardly any of the houses had phones. For the next 20 years the call boxes survived on passing traffic. Then came the mobile phone.

Now BT wants to take away the Wixoe box, and the village (population: not very many) is concerned. “Mainly we use it for giving directions,” says Sandra. “I'll say ‘next to the phone box' much more often than I'll say ‘across from the church'. I'd have to start giving my house number, I suppose.”

Dave Smith is a parish councillor and has lived here for 27 years. “Not long,” he says, emerging from his garden. He is trying to arrange for BT to leave the box, even if it takes away the telephone. The problem is, somebody has to be responsible for it. Somebody has to be insured. The glass could get smashed. A very inventive child could somehow get trapped inside. In modern Britain, public space can't just be left to look after itself.

English Heritage lists 2,800 red phone boxes across Britain but seems more keen on the K1 model, designed in 1921, and the K2 model, from 1924. As far as I can make out, this one is probably a K6, designed in 1935. These are not even terribly rare. Except in Wixoe.

So there it stands, surrounded by whitewashed stones and a little fence, next to a dustbin and a noticeboard sporting a timid boast about success in the battle to save the local post office. I didn't want to use the box. Journalistically it seemed irresponsible. But I didn't want to leave my post, either, in case somebody turned up to use it while I was gone. True, the odds were slim, but you don't want to miss a scoop like that.

The phone doesn't take coins, presumably so that nobody has to empty it once every 30 years. Using my credit card, I called Carol in Manchester. “It's mad here,” she said. “Loads of people. I think some of them may be drug dealers. In fact, there's a queue forming. I've got to go.”

And so she hung up, and I watched the spider scuttle back into his corner. Outside, an orgy of twittering blackbirds were flapping about in a puddle. Mr Taylor came past with Jasper, his big black labrador, and down the road by Mr Smith's house I could see the Suffolk Library bus, with nobody in it. And I waited, and I waited, and I waited, but nobody came.

HUGO RIFKIND

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