A white water rafting trip through the Grand Canyon is full of surprises.

The guides tie down your stuff in a dry-bag, so it stays safe and dry when the boat flips over. All I had to bring was clothing, a tent and sleeping bag.

The trip starts at the edge of Grand Canyon National Park.

The first surprise was the water – it was green, clear and shockingly cold – about 35°. It flows from the frigid lake-bottom behind the enormous Glen Canyon dam, upriver. The contrast feels pretty strange when you’re baking in 105° desert air, and the water is painfully cold. Some of the more experienced rafters brought fishing gear, and several cases of beer. They tied the beer into nets, and dragged them behind the boat – better than an icebox.

The first couple of days I was sometimes cold, even in the desert heat – the rapids soak you with freezing water, the river is often in shade, and just as you begin to dry out and warm up, you hit more rapids.

White water rafting can be pretty exciting. Some of the rapids are massive; you’ll need to paddle hard and follow orders. Sometimes there’s a touch of danger, but these tour guides know what they’re doing. I didn’t get ejected from the boat on this trip, but I did in Nepal, once. I remember holding onto my glasses with one hand, madly trying to claw my way to the surface with the other. Holding my breath, tumbling over and over…it was… excellent.

Breakfast on the riverbank: bacon, eggs, pancakes, yogurt, fruit, coffee. The captain was also the cook. The food was fine. He’d wake us early each morning with a long, loud call: Coofffeeeeeeee is Readyyyyyyy…. echoing through the canyon.

We camped on sandy river banks. You can’t pitch your tent too close to the river because the water level changes quickly, depending on the dam’s release schedule. It’s no fun to find the river creeping into your sleeping bag at midnight.

They set up a surprisingly comfortable chemical toilet behind some brush outside camp, and a jerry-rigged “occupied” sign system, but it’s only for number “two”, as they say. If you need to pee, the park regulations require you do it in the river. Easy for the guys, who can just stroll two minutes from camp, but a pain for the ladies who have to go wading in the freezing water. Apparently, the scientists have determined that peeing in the sand and soil in a desert clime does more long term damage to the environment than doing it in the river.

We’d take a couple of hikes up the side canyons each day. You need to pay attention to where you put your feet – I saw a few rattlesnakes.

My favorite part (along with the rapids) was hiking up the side canyons to find these perfect little Eden-like oases. You can’t really see them when you look down into the canyon from the rim, but lots of little rivers and streams carve their way down to join the mighty Colorado.

Sixty five miles in, the gorgeous Little Colorado river meets the Colorado. A stunning turquoise, nice and warm – it makes for more pleasant swimming the rest of the trip.

The river cuts through the earth’s history – each band of color in the rocks exposes a different era. The white ones near the top are 200 million years old. The darks ones near the river are ten times older. Pick up a rock that’s two billion years older than you, and make it skip.

It’s an idyllic week. If you don’t mind hiking out on the last day, you can do it for about $1500. Or, you can pay a bit more for a ride across Lake Mead to Vegas, if you need a change of pace.