The bulldozers on once-pristine hillsides serve as constant reminders of the more crowded, urbane region in North County's future.
Harder to find, but still all around, are the signs of history, dating back thousands, even millions of years.
When North County people think of the area's past, they usually conjure up memories of a rainbow of flower fields as far as the eye could see along Interstate 5 south of Carlsbad, of plump pumpkins polka-dotting green fields in the San Dieguito River Valley.
These sights are fading memories of the area's recent history, preserved only in photographs and nostalgic reveries.
The more enduring reminders of yesterday include cone hills that once were active volcanoes, gold mines and missions and rare dinosaur bones. And rocks that bear the imprints of art hundreds of years old.
North County's varied landscape contains a million witnesses to history; these are just a few to serve as guides into the colorful past.
Long before the coastal slopes and valleys were shaped into today's undulating North County landscape, creatures roamed the rugged land and swam the briny sea where tracts of expensive homes and clusters of industrial parks now stand.
The high land where Palomar Airport sits was a coastal island in those days--75 million years ago--and the ocean reached far inland to San Marcos.
As bulldozers dug into the hillsides to make way for houses, they unearthed fossils from that Cretaceous Period, providing paleontologists with a glimpse of ancient sea life inhabiting the area near where La Costa lies today.
Shells of ammonites, nautiloids, clams, snails and crabs were daily finds as grading advanced inland. The sea creatures, some of whom resembled a cross between a giant snail and a squid, were bounteous, as their fossil remains testify.
Then, in 1987, a San Diego Natural History Museum staffer was checking a newly dug sewer trench east of Palomar Airport and found, instead of the common seashell fossils, petrified bones of a dinosaur.
Brad Riney, the paleontologist who made the exciting find, had earlier found partial remains--a thigh bone in 1983, 13 tail vertebra in 1986--of a hadrosaur, or duck-billed dinosaur. His 1987 discovery was of a very rare armored dinosaur, or nodosaur.
It was during the construction of College Boulevard in southeastern Carlsbad, as trenchers dug down 60 feet and kicked up evidence of bone fragments, that Riney knew he had struck Mesozoic pay dirt.
"I saw it and I thought, 'Aha!' I knew that sucker was in there. And it was," he said of his discovery. It is the first time nodosaur remains have been found west of the Rocky Mountains and is one of less than two dozen finds in North America. Other nodosaur remains discovered in Kansas and Wyoming showed the same bony armor-plate covering, leading some scientists to speculate that the Carlsbad nodosaur was merely an early tourist who headed west with his peers.
Other paleontologists have argued that the scaly beast was actually a sea creature, although the size and weight of the dinosaur's bony armament belied its ability to do anything but sink like a rock in water.
Despite its impact in paleontological circles, the nodosaur was no great shakes in its Cretaceous Age. It measured probably no more than four feet in height at the shoulder, and stalked around on stubby legs, eating greenery and menacing no one. Its 12-foot length was made up mostly of tail.
The well-preserved thigh bones and rear leg bones are on display at the San Diego Museum of Natural History in Balboa Park. Riney's sketch of the way the beast must have looked is there, too.
Riney, who works as a paleontological watchdog on construction sites in San Diego and Orange counties, now has his eye on a steep bank on the edge of an Oceanside freeway. He already has found evidence of early primates in Oceanside's soils and anticipates that when that bluff falls to make way for freeway widening, "there will be incredible finds in there."
North County has it all, geographically speaking: mountains and desert, the pine forests and the sagebrush plains, fertile coastal slopes and sandy beaches.
As varied as the landscape is the history of the region and how it came to be a potpourri of photogenic mountains, stark deserts and coastal lagoons. Geomorphologists--scientists who argue and postulate about the world's landforms and how they came about--figure that North County was a part of the Pacific Plate, a massive piece of the earth's crust that traveled northward, stopping for a millennium or so to rest, then journeying on until it came to form the California coast. Its latest stop might be permanent, but more likely it is here just for a visit.
North County, and the rest of Southern California's coastline, docked on the North American Plate at the infamous San Andreas Fault about 20 million years ago, according to Monte Marshall, a professor of geology at San Diego State University.