I never thought I'd still be a runner when I turned fifty. I don't feel fifty but my fiftieth birthday is three months away, and here I am out on the lake path with the dogs and the skaters and the kids.

I'm hyper aware of age these days. I look in the faces of the other runners I pass, and try to guess their ages. This one could be mid-thirties. This one's a mere babe, a student, twenty-one at most. Oh my God, here comes a man who looks older than me! We smile at each other, as if we won the same award. We're this old, and we're still running.

I'm not a serious runner. I ran a 5K race a few years ago and finished in the bottom third. I'm a dawdling runner, a sightseeing runner, a stop-and sit-on-a-bench-and-admire-the-view runner. Sometimes I don't even run at all. I jog, or I run just long enough to get my heart rate up and then I walk.

I love it, my form of running. It's portable, and practically free. Swimming's great, but you need warm weather and a lake, or a health club. So's riding, but you need boots, breeches, and a hard hat, not to mention a horse. All you need to run is a pair of shoes.

I run at home and when I travel. I've run in New Orleans on early mornings, when I've had the French Quarter all to myself. I've peeked in hidden courtyards, and finished up in cafés with a beignet and a cup of chicory coffee. Sometimes the best part of the run is when it's over.

Sometimes the best part of the run is the scenery. I've run along the volcanic coast in Maui; through Hyde Park in London; in San Francisco by the Bay. But my favorite place to run is the Evanston lake path. I know every inch from Main Street to Northwestern and yet every run is different.

In the winter, the landscape is so dramatic. The beach is a photographer's dream: abstract sculptures of sand, snow, and ice; countless shades of grey and brown; a study in texture and pattern. And it's deserted. It's mine alone.

These days, spring is on the way. I feel it in the air. I see its signs. Shoots by a fence, a faint green fuzz on the trees, and open water that makes me breathe a sigh of relief. I feel like the water must feel, freed from the thick blanket of ice and snow. Soon it will be time to look for beach glass for my collection on my dresser. Soon it will be time to swim.

I can't wait for the warm weather, but I'll miss the solitude. In the winter, I don't have to worry about collisions or being run over by a bicycle. I can devote my whole attention to the scenery, or to the thoughts inside me. I make mental lists, I plan my next column, I think about my life.

I run through time and space, through what has happened and what could. I dream about getting my novel published, I dream about living closer to this view, I wonder what this year will hold.

I run by ghosts. I run by myself as a child playing on the beach, past my brother playing guitar on the rocks, past me and my friends watching the sun come up. I run through the years of my life.

My approaching birthday is in the wind like the change of seasons. I welcome it as if it's the warm weather coming. I dread it as if it's the winter cold. It's bittersweet, it's the theme of the year. I've been to two fiftieth birthday parties in two weeks, with more to come.

We joke about being wiser. We say to each other, "funny, I don't feel this old." What does it mean to feel this old? To be this old? I look to the landscape for answers.

The rocks stand there, mute as always. The waves lap on the sand. The branches sway in the wind, quiet save for the rustling of the leaves. The rocks, the waves and the trees don't care about age. To them, time stands still, time crawls, time is irrelevant. They just exist, they just are.

It's silent, but the landscape has answered me. Being this old doesn't feel right and it doesn't feel wrong. It just is, like the turning of the seasons. I can't change it or prevent it. I can only accept it the way the rocks receive summers heat, the way trees lose their leaves in autumn, the way water embraces ice in winter. And keep on running.