The burly men that stand on Christo Botev Street and around Macedonia Square swinging lengths of rope are an intimidating and puzzling presence. The ropes are clearly the tools of their trade with which they advertise themselves to passers-by, but exactly what that trade is remains a mystery to most foreigners and many Bulgarians.

The five that I interviewed on Tuesday afternoon were surprisingly amenable, and soon explained that they were 'hamali', or labourers, who specialise in moving heavy objects. The hamali, identified only by their coiled ropes and straps, either slung over the shoulder or swung by hand to attract the attention of passing vehicles, are traditionally Roma, and the profession dates back many generations. Two of those interviewed said that their grandfathers and great-grandfathers had been hamali, and four of the five had themselves been hamali for more than 20 years.

They are self-employed and work either individually or in groups, depending on the nature of the work offered. They are often asked to carry luggage, crates, or pianos, and use their ropes and straps to pull the heavy objects upstairs, or lower them down, usually favouring straps over ropes as they lie flat on the shoulder and don't cut into the skin as much.

Probably the most challenging objects to move, they all agreed, are safes, which can weigh up to a ton. Such work requires eight to 12 men and a great deal of haggling over the price, which I found they were very good at - towards the end of the interview one of them demanded 40 leva between them for their time. I countered by suggesting that they should pay me for making them known to Bulgaria's expat community, some of whom may well be in need of their services in the future. Fortunately they assented and reluctantly agreed to me buying them a beer each instead.

As for odd jobs, one hamali told me that the strangest job he had ever been asked to do was to carry a dead body. Another had carried a man in a wheelchair up several flights of stairs. It's rare for them to refuse any kind of job, no matter how big or small, but it depends, they assured me, on the arrangement they reach with the client.

Sometimes the clients trick them by paying less than the agreed sum, and sometimes they spend whole days waiting without employment, and that, they agreed, is the price of their independence. "We don't have any bosses and we like it like that," said one. "It's better to work like this because we can organise ourselves." But his statement was immediately refuted by another, who said that it would be better to have a boss, as it would mean that their health insurance and social security would be covered. "It's not good for us to work without insurance," he said.

Otherwise they love the job, which generally pays them enough to feed themselves and their families. "I've been here on Christo Botev Street for 26 years," said one hamali. "I've never done anything else and I don't have any complaints about the work. We're here every day of every season - people know us by our ropes, we work hard and help each other too."

When I asked what happened if they damaged or broke the objects they were paid to move, they responded with mock astonishment. "We never break anything," was their initial reaction. "We're masters, professionals, and are extremely careful, but of course," they added, "if we do break something we won't get paid."