Next up, Alexander. Now that's a challenge ...

Whatever else he was, Alexander was a great tourist. No one had travelled a route like his before. From Greece to Samarkand and back across the vicious Makran Desert, Alexander trailed his army of Macedons on the ultimate gap-year adventure. In fact, it took the King of Macedonia eight years to trek his way through what are now Turkey, Syria, Lebanon, Israel, Egypt, Iraq, Iran, Afghanistan, Uzbekistan, Tajikistan, Pakistan and India.

No doubt Oliver Stone's forthcoming film is going to inspire a few people to leap on horseback and follow in the King's hoofsteps but they won't find it easy. I decided that the best way to go about planning such a route today was to talk to Carl Jackson at Global Village, a company which has looked at some offbeat treks for me in the past. "Not easy," said Carl. "His route has some obvious issues. Firstly, you can't cross the Golan Heights between Israel and Syria like Alexander did. And if you do go to Israel you won't be able to enter Syria or Lebanon or Iran if there's evidence of travel to Israel in your passport. I know it doesn't sound very rock'n'roll having Alexander amend his campaign due to visa restrictions, but today's traveller doesn't quite have his influence."

Carl was also wary about passing through Iraq to Baghdad. "It will cost you a fortune. The world's most expensive taxi ride is from Baghdad airport to the Green Zone - £6,000. Unless he's got a really big budget I think your modern-day Alex had probably better skip Iraq, too."

Fortunately the first stage of Alexander's 2,000-mile journey of conquest is not difficult to follow. Carl reckoned on starting the journey with a taxi from Pella (the old capital of Macedonia) to cover the 39km to Thessaloniki, then a bus to Alexandroupolis, a taxi to Ipsala in Turkey and a third local bus to Gallipoli, where I could make a 50p ferry trip across the Dardanelles and be in Asia within 24 hours.

Alexander was looking to take on the Persian King Darius III; his first opportunity to do this was at the Battle of Issus near the Gulf of Iskenderun. These days it's in a nasty industrial part of southern Turkey. We could follow his route to war pretty exactly with buses to Izmir, Fethiye and Antalya for just £22. The only problem was this would mean spending 25 hours on buses in three days.

But that's just the beginning. Back in 333BC King Darius escaped and Alexander pursued him into modern-day Syria where he occupied Damascus. He then headed south down to Jerusalem and over Sinai to Egypt where he founded Alexandria. Aware that an Israeli stamp in my passport might wreck any chances of following the Boy Wonder all the way to Samarkand, I agreed we'd take a bus as far as Damascus (£25) and then an Egypt Air flight down to Cairo (£92), hole up at the Windsor Hotel and take the train to Alexandria (£3) where I'd splash out on a room at the Hotel Cecil.

Alex's next stop was out in the desert, at Siwa Oasis. This, Carl reckoned, we could do with an uncomfortable eight-hour bus journey (£4), then we'd retrace our steps as Alexander did, omitting Jerusalem for obvious reasons, heading through Damascus and cross the Euphrates to Arbela. However fast I moved, I would now be into my second week. By the time he got to Arbela, however, Alexander would be two years into his epic trek. All that founding of cities and besieging of cities takes time.

At Arbela Alexander was looking to finish off Darius for good, which he did in 331BC at the Battle of Gaugamela, entering Babylon (modern Baghdad) in triumph. As I could do it only in a very expensive taxi we decided against it. Instead, I chose to fly to Shiraz (£500) and overnight at the Shiraz Eram Hotel before taking a £22 excursion the next day to see Persepolis and Pasargadae, catching up with Alexander as he pursued the vanquished Darius. "Mind you, Iranian visas are a headache," said Carl. "And getting a multiple entry one will prove tricky. And we won't be able to obtain a visa for entry into Pakistan from Iran. They're worried about insurgents trickling into Baluchistan." I was beginning to think Alexander had the right idea. Nothing cuts through local bureaucracy like a very large army.

Alexander reached the Caspian Sea in 328BC and founded another Alexandria, now known as Margiana or Merv. Then he founded a third, known as Alexandria Arigrum (modern-day Herat). This is in what is now Turkmenistan. Carl reckoned he could get me part of the way by bus to Mashad (£2) and by shared taxi to Merv, assuming I could get a visa for the paranoid state of Turkmenistan. Thereafter, I was on my own as his expertise didn't extend to getting me over the Afghan border into Herat.

Fortunately, Paul Clammer of Kabulcaravan took over at this point. He knew the road to Herat well, having travelled it in a minibus himself two years ago. He also knew that a lot of what Alexander accomplished just wouldn't be possible now, because these days the only people allowed to cross over from Alexander's Bactra (the modern town of Balkh) into old Samarkand (Uzbekistan) are members of the UN. So we settled for a simplified route that followed Alexander's progress along the Kandahar highway (mercifully rebuilt by the Americans) past the new airbase at Bagram and into the Hindu Kush.

We know that Alexander built a fort at Arachoton (today's Kandahar) and then headed on to Ghanzi via a road that Paul said he could not recommend because of Taliban presence. We would not be able to get any further than Balkh, he said. So from there we would be turning towards Termiz.

I was sorry not to be able to follow my leader any further, but 2,000 years ago his own troops made it pretty clear that they were not going to either. Altitude sickness, the intense cold and lack of food caused a near-rebellion and Alexander agreed to take the army back south down the Kabul river. We were able to follow him out of Afghanistan, Paul said, by taking a shared taxi down the road that runs along the side of the river. That way we'd end up eventually in Pakistan. In total the Afghan leg would cost me around US$500 - and it would have to be dollars - travelling overground but, on reflection, Paul felt some of it really ought to be flown as there were sections that he didn't consider safe.

The last section of Alexander's journey was across the dreadful Makran Desert back towards Persia. Some historians suggest that Alexander chose this route to punish his rebellious army. Carl reckoned I had two choices. Get a bus from Karachi via Turbat and Bela to Gwador, from where I'd be able to commission a taxi through Baluchistan (a semi-autonomous region ruled by warlords and opium barons). Or take a train from Zahedan, which would deliver me 22 hours later into Tehran for about £20, assuming no opium-crazed warlord stormed the train.

On the whole I thought it might be best to come home direct from Karachi. Not much point in going on to Tehran, because Alexander didn't actually end his travels there. He made it back to Babylon before succumbing to food poisoning, the curse of backpackers everywhere since time immemorial.

On the whole I took that as an omen. This was one journey best travelled in the imagination.

Contact Carl Jackson via and Paul Clammer via 'Alexander' is released on 7 January