A trek to the towers.

We'd hatched the plan over beers, of course. My friend and I would trek the length of Broadway, Manhattan's longest street. We'd start at 216th Street, near where Broadway empties onto a bridge to the South Bronx. Our destination would be Battery Park, 13 miles away, at the southern tip of the long, skinny island that's Manhattan.

The February day we chose was foot-stamping cold. We'd bundled up, with hats, gloves and scarves. I wore long johns, and my Yankee friend teased me about being a wimp. But as we got off the subway in Inwood, our breath was like smoke in the morning air.

Later in the day, we both would've been uneasy here, a couple of Columbia students wandering among tenements once known for gunplay between Dominican drug dealers. But on Sunday morning, the neighborhood slumbered. The quiet made the graffiti-covered walls seem more improvised art than scrawled anger.

Thirty blocks of walking took us to Washington Heights and the St. Jesus Pharmacy; I had to snap a picture of that. Twenty more put us in front of the American Numismatic Society. Neither of us knew what "numismatic" meant. Something to do with theology maybe? So much for grad school. "Coins and coinage," a bronze plaque on the building told us.

When we crested the hill at 135th Street, in Harlem, I got a clear view of the tops of the twin towers of the World Trade Center. They were far away and Tinkertoy tiny.

From there, the towers became a beacon. You can't see them from many spots along Broadway. Manhattan's glass-and-concrete canyons make it hard to see anything other than the skyscraper right beside you and the quick-stepping New Yorkers usually thronging the sidewalks. But here and there, the towers would reach up through the crowd, like sunflowers on the far side of a summer garden. Each time, they grew a little bigger, telling us we were closer to a celebratory piece of apple pie at Bubby's in TriBeCa. The sky was Carolina blue and clear. The towers' sheer white sides gleamed in the sun.

Eight hours after we started, we'd made it to the Financial District, and dusk gave just enough light for a snapshot of the Trade Center looming above us. We were a block east, in front of St. Peter's Church. A wannabe Alfred Stieglitz, I used the church's steeple and roofline to frame the North Tower.

A few weeks later, in a bookstore, I found a postcard of the same view. The light was better; the colors, richer. But the frame, the same. I bought two: one for my buddy, one for me.

Little did I know that that those gleaming towers could be beacons for terrorists, too. Or that that postcard would become a memorial, rather than a memory.