Sitting cross-legged under a tattered plastic tarp, a young Mexican man stopped strumming his guitar to smile and wave at the giant "globo" gliding above the bushes of his trash-strewn camp. Moments before, a group of boys playing basketball on a sprawling Rancho Santa Fe estate seemed oblivious to the 13 hot-air balloons floating high overhead in various air balloon rides.

Such are the contrasts seen daily from the skies over North County. Stretching from the Solana Beach coast to the desolate fields west of Rancho Penasquitos, this strip of land known as "the corridor" is San Diego County's most popular launching and landing site for hot-air balloons, "globos" in Spanish.

At least a dozen balloons float over the area twice a day in different air balloon rides, just after sunrise and about an hour before sunset. On a clear day, balloonists take in a magnificent 360-degree view spanning from Oceanside to the Coronado Islands to the mountains near Julian.

But what they also take in, and what isn't mentioned in balloon brochures, are the clumps of makeshift migrant-worker camps dotting the fields east of Del Mar. "It's kind of like (the passengers) are surprised and they're shocked," said Brian Moody, manager of A Beautiful Morning, a Del Mar hot-air balloon company.

"A lot of them think there's no life east of I-5, let alone those desolate fields filled with Mexican workers." The balloons usually take off from a field near Manchester Avenue in Cardiff and travel southeast over posh Rancho Santa Fe and Whispering Palms before landing in the fields near Black Mountain Road. One balloonist jokingly refers to the route as "the Realtors' tour."

At a maximum altitude of about 1,800 feet, the balloons float over sprawling mansions, clear-blue swimming pools, horse corrals and golf courses before descending over fields crisscrossed by rutted dirt roads known as "the Mexican highway." On a recent evening just before sunset, dozens of migrant workers stared up at a passing balloon, waving their arms and yelling greetings lost in the wind.

When the balloon touched down, about 12 workers, some on bicycles, rushed to the landing spot and helped the pilot, passengers and crew dismantle the balloon, basket and propane fuel burners. "The truth is that the workers are very friendly and they like to help us out when we land, but the landowners are very uptight about it," said Tiemo VonZweck, owner of the Skysurfer Balloon Co. in Del Mar.