Bridges to jump off, for every girl and boy.

It's sometimes easy to forget that we're surrounded by water. Besides the outer-borough beaches, few use this water for recreation. The rivers and bays have a dull, washed-out appearance, and when you look down, it seems like undulating wet cement.

Seventy-six New York bridges connect neighborhoods and boroughs separated by water (of more than 2000 total). Try and name those bridges, and the biggest, most celebrated names come easily to mind: Brooklyn, Williamsburg, Manhattan, Verrazano, 59th St., George Washington, Triborough, Throgs Neck and Whitestone. Then, a pause.

Although hundreds of thousands of people cross the Henry Hudson, Cross Bay Veterans Memorial, Roosevelt Island, Wards Island, Third Ave., Madison Ave., 145th St., Alexander Hamilton and Willis Ave. bridges every day, many don't realize it. We're like that: Just get me where I'm going and make it quick?who cares if there's water down there?

To visit the oldest standing bridge built in New York, you have to go to mainland America: the Bronx. In the 1830s, New York's population explosion was centered in downtown Manhattan. Fire and disease were common problems, and the lack of clean water?in a city surrounded by water?was threatening to destroy the town. In the late 1830s construction began on a bridge over the Harlem River. It would be part of the old 41-mile-long Croton aqueduct; when finished, it would carry fresh water from upstate into Manhattan.

It took about 10 years to complete the stone bridge. People traveled uptown to 174th St. to marvel at the masonry pier and arches, 135 feet high, 620 feet wide, 1450 feet long. In 1848, it was nicknamed the High Bridge. Water was carried via the structure, and the top had a walkway for pedestrians and horse and buggies. As New York grew, the bridge and surrounding neighborhood became known as Highbridge.

By 1923, the structure had become an impediment to shipping, so the Roman-style arches were replaced with a single steel span across the river. In the following decades, scores of other bridges were built to accommodate growing automobile traffic. By 1949 Highbridge was no longer used to carry water, and because it could only carry pedestrians, it became a quaint reminder of a simpler time.

In the 1970s, Highbridge became a crime district, with the bridge playing a starring role in the murder of a German tourist. As the Circle Line chugged under the span, two local kids dropped rocks down on the boat and killed a man. To prevent another such incident, the city erected a steel wall topped with barbed wire. It sat in the Harlem River, closed and unused, serving no function. It still does.

"I remember that," says John Daly, who lives on Long Island but grew up in Highbridge. "Kids used to go out on the bridge and shoot fireworks at the passing boats. Then they started to throw rocks, and the city waited until someone got killed before they did something about it. Crime and drugs ruined the neighborhood. It's a shame, because that was a great place, but the criminals ran people off and the city let it happen. My mother got her head smashed in the lobby of our building, and that was when we moved."

Highbridge, north and west of Yankee Stadium, is a district of long, curving hills. The neighborhood rises until you hit University Ave., where it slopes down to the Harlem River. It's a safer area now, but still hurts: The unemployment rate is around 17 percent, and the median income is below $20,000. I recently went up to the Bronx and worked my way to the west end of the borough.

To reach the bridge opening, I drove down Sedgewick Ave. On my left were hilly woods with a few stone staircases leading up to Highbridge Park. I drove by the old Yankee Motel?a once-famous no-tell motel?which is now the Bronx Family Center. Nearby is the Bronx Task Force to keep all the kids safe.

I turned onto University Ave., parked and walked down the block. It is a long spooky block even in daylight, with a 15-foot stump of an oak tree standing guard like a totem pole. The parkland on the left is used as a dumping ground, with one section seemingly dedicated to the dumping of old wooden doors. I was amazed by the white, green, blue and pink doors stacked next to each other.

The only people on the street were a crew of gypsy cab drivers taking a break and drinking coffee. I passed an apartment building with a score of satellite dishes attached to the front windows, and another building with igneous rocks out front as some kind of nature statue. I walked by an old stone Catholic church with figures of saints carved into the side; it's now home to a drug program, Samaritan Village. I heard gospel songs inside, but no one answered my knocks.

Nearby is the newly cleaned up Highbridge Park, a swath of green that has a neat, and clean walkway and cement checkers/chess tables with matching stools. I walked up to the painted black steel of the bridge and found the door sealed shut. Along the sides, razor-sharp barbed wire keeps out vandals and thrill-seekers alike.

"You can't get out there, son. Been sealed up for years."

I turned to find Paul, an older man who has lived in Highbridge for, as he put it, "too long." He likes to come down to the park and meet other seniors during the day to play dominoes.

"I don't come out here at night. The young kids got no respect and they'll hurt you. I'm too old for that."

He sat down on a cement stool, let out a long sigh and looked up at the gray sky. I asked him about the bridge.

"Well, it is high, isn't it. Be nice if they ever open it back up and you could go out there and get some fresh air. I'd like to see that happen."

Does he think that's likely?

He gave me a small smile, shook his head. Then he turned and walked away.