BAJA CALIFORNIA SUR, Mexico _ Chances are you'll be luckier than I and you'll get a warm day when you visit the ancient paintings at Baja California's La Trinidad Cave.
But I was there in the cool of January and gritted my teeth as I dived into the cold river that meanders through a canyon of rock the colors of chocolate and cinnamon.
This is a rite of passage _ quite literally _ required to see the fascinating prehistoric images at La Trinidad, named for the three-peaked mountain above the canyon.
Guide Salvador Castro Drew's email the day before was terse and slightly mysterious: "Meet at the town arch at 9 tomorrow and bring your swimsuit."
That all became clear after a bumpy, four-wheel-drive journey across the desert and a 20-minute hike during which we examined petroglyphs at trailside.
The river wasn't wide, but it was deep enough to require swimming to reach our destination. Giant boulders were conveniently placed to provide privacy as other tour-goers and I changed into our swim togs.
Splashing out at the far side, Patricia Berman, visiting from Corvallis, Ore., announced, "Whoo! I've been known to jump into mountain lakes, but usually I've been hiking all day and I'm hot and dusty and it's 90 degrees out."
But as we shook like wet dogs and climbed to the cave site, we saw that it was worth it.