I celebrated my 50th birthday a few years back by just about killing myself on a desert hike. I lived atop a 3,000-foot plateau called Grapevine Mesa, an extraordinary place that towered over the far eastern end of Lake Mead, a huge man-made body of water that sprawled through desert canyons 80 miles distant. My then-husband, a ranger with the Park Service, was working that day but knew I planned a descent from our mesa to the reservoir below, a six-mile hike I’d been dreaming about.

Nearly a half-mile down, my route -- picked out carefully from a topo map -- started following a draw that I was pretty sure would lead gently through a looming ridgeback. Suddenly, a drop-off appeared, one called a dry-fall in these desert regions. It was only about a 10-foot drop, but there seemed no way around with slick canyon walls abutting on both sides. I looked over the fall in search of bighorn sheep droppings on the canyon floor below. None. Not a good sign. I might become trapped, not able to go forward or back. My better judgment said to backtrack; my reckless judgment said, "But you might miss something really interesting."

I loosened the pack and dropped it over the dryfall. Then, poised on the over-hanging lip, I jumped, landing with a jarring jolt into the sands below. The risk immediately seemed worth it: The narrow and winding canyon walls became more enchanting with each turn.

Another turn in the deep gorge brought reality back as a sheer precipice appeared at my feet, one 30 feet straight down. I sat on a granite boulder, took a swig from the water bottle and settled in to think. After studying the cliff faces, I noticed a ledge about three inches wide crossing the perpendicular wall. I approached the narrow ledge to take a closer look, then peered down toward jagged boulders below. I then began edging slowly along the cliff wall, hugging the smooth surface. No turning back now. About midway, I began teetering dangerously backward. I hesitated, breathing carefully. The backpack had to go. With delicate effort, I carefully slid one arm from the pack, then slowly, the other. The pack landed with a clatter. The sound was unnerving.

But the remaining balancing act became easier, and finally, I gained some boulders. The narrow gorge widened into a gentle open valley below, and the descent became a stroll. It felt great to be alive in the thin dry desert air, to take in the silence and see forever. I felt privileged to be in this grand place. Soon I approached a smaller ridge of rocks and passed through with no problem. Bighorn Sheep droppings were abundant along the draw. The last mile was an easy walk down a rock-bedded wash.

The sun was high overhead and hot as I reached the shoreline in a secluded cove. The crystal blue water looked delicious and inviting, so off went the boots, the socks, and finally, my shirt. I just had to sit and wait for my ride. My husband would be patrolling the lake along 20 miles of shoreline that day and would pick me up wherever he found me. I stretched out on a flat white boulder.

A pebble turned from somewhere back up the wash. Must be a bighorn coming down to water. Another rock turned, this one closer. I thought, "That’s an unusually noisy bighorn."

I rolled onto my side to see a young man from nowhere, who came to an abrupt halt when he saw me. I said what seemed natural: "Hi." "Oh, excuse me!” he blurted, and fled back toward where he’d come. A topless older woman was probably not what he’d expected to see around the corner.

A half-hour later, I heard the familiar drone of the Park Service boat, and there was my husband, who seemed in good spirits as he pulled to the shore. "You won’t believe what happened to me awhile ago,” I told him.

"Oh, but I would," he replied. "I just talked to a young fellow in a kayak in the next cove. He wanted to report coming across a woman who was absolutely alone, stranded with no boat, and sunbathing partially nude. I told him not to worry... that it was probably just my wife. She’s out here having the time of her life -- celebrating her 50th birthday."

Mary McBee is a contributor to Writers on the Range, a service of High Country News (hcn.org). She’s still hiking and climbing in Tama, Iowa.