"YOU CAN reach 17 cities in North America from Heathrow" - British Airways ad, 1989

And you still can. But the list has changed substantially in a decade.

Anchorage has dropped off, since flights to Japan now go non-stop. Orlando shifted to Gatwick, as did Pittsburgh - but this month BA's boss, Bob Ayling, implied the latter route was the pits, and would disappear when the summer schedules end in October. Tampa, which proved an expensive waste of time when it was "bolted on" to the Miami flight, was eliminated, but then revived from Gatwick last year.

So what are the new arrivals? In the US, Newark, New Jersey, which appeared initially as a response to Virgin Atlantic's service from Heathrow. In Canada, Calgary and Ottawa, though flights to the Canada's capital are operated on a code-share basis by Canadian Airlines.

The makeweight is Mexico City, which is technically in North America and therefore allows British Airways to maintain its score of 17 cities. But the route is one of BA's most chequered. It originated as a Gatwick- New Orleans-Mexico City operation, which lost money as fast as the peso lost value. Then it was revived as a Heathrow-Mexico City non-stop. Next it was moved to Gatwick for a year, and finally settled back at Heathrow.

Nine other airlines operate across the Atlantic from Heathrow, but only one carrier offers destinations that BA does not fly: Air Canada, to St John's and Halifax in Nova Scotia.

For the best choice of destinations, Gatwick is now a better bet. With the addition this summer of Continental's flights to Cleveland, the Sussex airport now boasts services to a score of US cities, plus charters all over Canada - and BA's new service to Cancun in Mexico.