Flecks of blood started to appear on my sweat-drenched pants as I watched the railroad ties thudding away beneath my bike tires. The thorns I’d wandered through a few minutes earlier and a chain-link fence separated me from the little circle on my GPS I’d been trying to reach for the last hour.

The quickest way around was along the tracks, and I shot nervous glances behind me to watch for the train I had a bad feeling would send me diving back into the pointy undergrowth.

While I huffed toward the next crossing, I realized that this was not the way most people spend an afternoon in Memorial Park. About 1/2 mile ahead of me, lithe joggers ran contentedly along the boulevard. Yet there I was, practically in the shadow of the Williams Tower, having an outdoor adventure in the heart of Texas’ largest city.

A curiosity about geocaching and a few dumb turns may have led me to that particular place and time, but something more universal made me enjoy it—the simple pleasures in being outside and experiencing something new.

Whether it’s an afternoon exploring the Hill Country vineyards, a historic audio tour of downtown Houston or a few mauls at a pick-up rugby game, I’d like to fill this space with a new way each week to get out of our city’s legendary air conditioning and do something worthwhile outdoors.

Take geocaching. Following an impulse buy at REI, I turned to this quirky hobby to break in my new GPS. It seemed straightforward: just enter some coordinates and hunt for a hidden container at that spot. Sites like geocaching.com catalogue thousands of caches all over the world, ranked by terrain and difficulty.

“I go to see the location, to go to the place, to see someplace new,” says Jim Evans of Clear Lake. Known by the caching alias "Thot," Evans hosts a helpful site for beginners here.

What the GPS doesn’t tell you, as I found out, is the best way to get to a cache or where to look once you reach the 30-foot circle that marks the limits of your device’s accuracy.

I set out from my house thinking I could cut through the park, hop across the tracks and make my first find with relative ease. Trying stubbornly to draw a straight line across the handheld’s screen with my movements, I crossed a road-bike track, stumbled onto some excellent mountain biking trails and scrambled across a ravine before finding myself riding down the railroad.

I made it off the tracks without incident, but by then my new menace was the sun, perilously close to setting while my GPS made threatening beeps to let me know the batteries were running low.

The hunt led me into the Houston Arboretum and Nature Center, past a lovely set of ponds where lovers chatted on benches. I likely never would have discovered it on my own.

A bike in one hand, my GPS in the other, I again headed blindly into the bush, pushing through branches, starting to fear that I’d come so far, actually circled this thing at one point, only to have it slip my grasp in the approaching twilight.

Just as my hopes were starting to fade, I spotted an ammunition can painted green and black beneath a log I was about scramble across. I took a seat, sucked down half a bottle of Gatorade from my pack and opened up the container.

Inside were old McDonald’s toys, a few pre-Euro French francs, custom coins bearing the marks of other geocachers and a small notebook chronicling the discoveries of those who’d shared in this not-quite-buried treasure before me.

I hadn’t climbed a mountain or traversed the wilderness, but I still felt like I’d accomplished something as I wandered back to the road.

As the sun set, I cruised on home along Memorial Drive tired and happy, just in time to see the train barrel past at full speed.