'Are we really allowed to do this?'
'Seriously?" The look on my brother's face was priceless: are we really allowed to do this? But this is Cambodia - you're allowed to do a lot of things.
We wandered out of the airport into the throng of touts, their pleas piercing the muggy air.
"Sir, taxi! Friend, motorbike taxi! Hey, where do you want to go?"
Striding the confident stride of someone who'd been doing this for all of about two weeks, I picked out a couple of guys with motorbikes, explained where we wanted to go and negotiated a price. My brother still looked sceptical.
"What about our backpacks?"
I shrugged. "Just wear them. Put your daypack on the front and your backpack on your back."
So we humped our bags on, plodded like canvas-covered turtles over to the bikes and sat astride them, each with a Cambodian guy on the front who thumbed the starter and revved the engine.
The look on my brother's face had changed. There was no more disbelief, just joy: this is great.
We spent about half an hour on those motorbikes, half an hour darting through snarls of Phnom Penh traffic while clinging to the bike's steel bars and listening to the driver's offers to provide increasingly illegal activities.
We could take a tour of town, they yelled over the noise of the traffic; we could shoot guns, we could visit "killing fields".
We could be supplied with any drug of our choice or we could be taken to "meet girls".
All this in the honk and shout of Asian streets, both of us helmet-less, amazed.
You never forget your first time in Asia. I doubt my brother will ever erase from his memory the wild abandon of that first motorbike taxi ride to a dump of a hostel down by a lake.
I was playing it cool but two weeks earlier I'd been as wide-eyed and gaping as him.
I'd thrown myself into Asia's deep-end then, electing to have my first experience in the continent in one of its busiest, craziest cities: Hanoi. I was 24. Not only had I never travelled in Asia before, I'd never travelled solo through a non-English-speaking country before.
I had little idea of what to expect: what I'd be seeing, what I'd be eating, who I'd meet, where I'd go.
My first step into Asia wasn't on the back of a motorbike but in a Vietnamese taxi, which took me into the city for probably double the amount I should have paid.
I can remember sitting in the back seat gazing at the madness of it all: the ridiculous traffic, the noise, the rubbish, all the skinny buildings that looked half-finished.
Every time the taxi would stop in traffic, coming to a halt in some area of the city so foreign and strange and intimidating, I'd think to myself, "I really hope this isn't my hostel."
Eventually, the car made it to Hanoi's Old Quarter, a more welcoming place for a tourist but still mind-blowing to someone who'd never been to Asia before. Everything was new and amazing, intoxicating and frightening. And all unforgettable, as Asia was then and always has been since.
You never forget the smell of travelling in Asia. One minute it's delicious, the tang of frying food or the waft of fresh herbs from a market. The next minute it's stunningly bad, an open sewer by the side of the road or a cloud of exhaust fumes from a clapped out old bus.
You never forget the noise of travelling in Asia; the honk of horns, the yell of touts, the ding of bells, the chant of monks, the electronic chimes at a train station in Japan.
You never forget the sights.
You never forget the first scooter you see carrying a family of five. You can't shake the pictures of marketplaces, of metropolises, of villages and little country towns.
Two weeks in Vietnam was my crash course in Asian travel. I figured out how to use a squat toilet on my first day. I was conned out of $100 on my second.
I honed my haggling skills, taking them from "appalling" to "still really bad". I marvelled at the freedom that comes with chaos. I saw stereotypes broken and some confirmed.
I tasted the best food I'd ever had. I got drunk. I got sick. I rode in rickshaws. I made friends.
I smashed the language barrier with karaoke.
And by the time I met my brother in Phnom Penh I knew what you could and couldn't do in Asia.
You couldn't expect things to go to plan. You couldn't depend on every day being easy. You couldn't expect to be unaffected by a continent that seemed to press
in around you, to shake you and tug at you and give back as much as it takes.
But you could ride into town on a motorbike.
The writer funded his own travel.