Here's a tip: When an eight-wheeled military transport vehicle is the only other vehicle you've seen for an hour on a Thai "highway", turn around. Immediately.

The plan was to drop Camille - she owns the cat we're looking after while she's on a three-month holiday -- at the airport. Not to catch a flight, but to start her overland bike trek across the narrow stretch of middle Thailand. We hit the sack early Friday night, knowing she wanted to be well on her way before the afternoon rains hit.

When we awoke Saturday morning, Camille greeted us with a proposition. "Instead of taking me to the airport, how about we go on an adventure?" We're always up for adventure and the opportunities therein, so naturally we said yes.

Rather than drive south to the airport on Route 4, we'd instead take Route 4005, an intra-province highway, first east and then south, following along a 40 km drive winding path through the unspoiled and majestic Ngao Waterfall National Park. Eventually, we'd wind up in Pak Song, where Camille would start the first leg of the bike trek. We, in turn, would drive the truck around, making a big circle to complete our leisurely drive through the rain forest of Thailand's Andaman Coast.

What's that saying about the best laid plans again?

We started out in familiar territory. We passed the hot spring and several little villages that border Route 4005, eventually stopping for a quick look around Ranong Canyon, an old tin mine literally blasted from the surrounding rocks, leaving a series of depressions that filled in with water over the years. It's been abandoned for years and has become a peaceful and serene place, but not somewhere you'd want to spend more than a few moments, so we carried on.

Just past the canyon, signs of civilization grew sparse as the jungle grew thicker, and some early rain showers moved in. But no worries -- we were on an intra-province highway, with solid blacktop. We could handle a little rain.

About 5 km later, the blacktop ended. The road continued; now just a well-maintained dirt (and stone) road. Still, the highway markers remained visible, and plenty of signs of other's passing were evident. No, the truck wasn't four-wheel-drive, but it was high-clearance enough to take on a few stones here and there. Plus, Google Maps said go forward, so...

Not quite what we'd consider a "highway", but...

(Astute readers will now be shouting "This is the place you should have turned around, Evo!" Less astute readers will agree momentarily.)

An hour later, we'd made it only an additional 5 km. Some of that is due to our lack of hurry: We didn't have much of an agenda beyond getting Camille to the 4006 junction, and she had plenty of first-night-stop options ahead of her. Some of it was due to the amazing vistas as we climbed ever higher into the rain forest, as we stopped for several photo opportunities.

But most of is was because the road was really, really steep, winding its way up and over the various mountains -- yes, mountains, not hills -- that make up the national park. And with a truck with over 300,000 km on the odometer, we weren't trying to qualify for the Thai rally racing team.

At one point while we were either taking pictures or peeing, we were overtaken by the Thai analog of a Unimog, its driver and passengers looking quizzically at the three Europeans and their tiny, laughable mini-truck. Had I not been taking in the sights, I would have thought "what an odd choice of transportation for an intra-province highway" and likely suggested we were out of our league. But I did not. [sigh]

After somewhat of a harrowing slide/crawl down a particularly steep and particularly winding stretch of "road", we encountered the Unimog again at a river crossing. While Camille conversed with the driver -- she speaks Thai -- I reconnoitered the river (really just a largish stream) and the road beyond. Both looked passable.

In the jungle, water crossings are the least of your worries.

The driver didn't hold much hope for us going either direction. The way forward was long, rough, and not all that often traveled. The way back rather steep, which earned us the odd looks from earlier. Our merry band of three reached consensus that forward was the right option. We were wrong.

The well-maintained road soon deteriorated to little more than a set of tracks leading through the jungle, with flora growing tall enough between them to cast serious doubts in our minds as to when it was last traveled. But we didn't relish going back up the road we came, so forward we pushed. And by "pushed", I mean there were two times I had to get out and push the truck, giving it just a little more oomph to get up a hill.

At the 26 km mark, the wheels almost literally came off the journey. Ahead of us was a hill as steep as anything we'd been down previously, but much, much longer. The rocks were large and loose. The ground underneath wet and made of clay. Not a good combination.

Giving it all the truck had in her, we made it about 80 meters up before gravity won out over friction and power. No amount of pushing would let the tires gain purpose, so back down the mountain we slid. Yes, slid. Big rocks conspired to snap a tie-rod as the front wheels stayed brake-locked, but Camille managed to get it back to the base of the hill mostly on track.

For our second attempt, it was decided that Sheila and I would wait near the crux-point of the last failure, pushing from the rear as the truck sped (?) by. At least that was the plan. It was a miserable failure, and the truck stopped again at exactly the same spot, spinning tires on rocks sharp enough to be used as hand axes.

After more back sliding, a new plan was in order. This time Sheila and I would ride in the back of the truck until momentum slowed. We'd then hop out -- on to the loose boulders resting on wet, slick clay, remember? -- and then push. Because there's no way anything could go wrong with that plan, right?

Sheila, as is often the case, was the voice of reason. Even if we could get the truck past the sticking point, we we'd still have to keep pushing the truck another 200 - 300 meters over equally challenging terrain. And since neither of us is secretly Magnús Ver Magnússon, she had a point we couldn't deny. [sigh]

With a heavy heart, we headed back the way we came, more than a little disappointed that we were stymied with only 12 km to go. And more than a lot worried about the truck's chances of getting back up the crazy hills we'd just slid down a few hours before.

Luckily, the driver of the Unimog was overstating the steepness in our return direction, because I only had to get out and push once. He must have been originally from the south of France, I suppose. (Inside joke.)

We made it back to Ranong a little dejected, a little tired, and a lot hungry. After lunch and making a mechanic appointment for the truck on Monday, we finally delivered Camille to the 4006 junction, this time via the easy (and a little boring) highway, Route 4. As Sheila and I passed by the 4005 turn off on our way back, I was a tempted to see what we would have faced on the other side of the crux point, just 12 km away.