Both were pioneers: Breece in the wilderness, Jane Jacobs in an urban frontier that she could see in a way that others had not.

The enterprise zone concept sees inner cities, in effect, as 'urban frontiers' constrained by regulations and a tax code that is irrelevant to the problems and opportunities that exist.

The waterfront itself has always been a wild place, an urban frontier where the laws of society are suspended.

Then, in 1832, with the northern stretches of the urban frontier nearing 14th Street, Houston Street became the southern boundary of the new 15th Ward.

And so is the week's refrain - this is a safe haven, these are the best schools, the best people, the best neighborhoods scratched from farmland at the far urban frontier.

The Irish on the urban frontier: Nineteenth century Detroit, 1850-1880 (1976)

But the couple called the space home for 27 years, rearing two daughters as they watched SoHo's gradual evolution from urban frontier to upscale address.

It's kind of like being a cow girl in the city, on the urban frontier.

But everyone agreed it was a true urban frontier, a gritty world of garbage trucks, dying factories, snaggle-toothed hookers and scorched carcasses of stolen cars.

Beyond dispute is that another urban frontier, resistant to change even in the robust market of the 1980's, is at last being breached.