When you hear that one man is responsible for the death of 17 million people it's probably natural to want to make absolutely sure that he's dead.
"You can't go in there", says the burly Uzbek guard, his gossamer eyebrows scrunching together in contempt.

Lacking even the most faltering of Russian I take a risk. Preferring a modest fistful of tattered so'm banknotes I raise an eyebrow in what I hope is interpreted as a masculine invitation to minor corruption rather than a sexual come-on.

I'm out of luck. Snorting with impressive derision he walks away tutting. The heavy door to the crypt remains locked and the trail goes cold. The Central Asian sun ratchets up another notch as I seek sanctuary under a mulberry tree. It's lunchtime in Samarkand, Uzbekistan and I'm on the trail of quite possibly the ultimate warrior bad-ass of all time.

Amir Timur, or Tamerlane as he was often known, was a man who makes Idi Amin look like a Dutch social worker. He makes Ceausescu look like a Unicef volunteer. He makes Genghis Khan look like a lily-livered fop. Timur made pyramids out of the skulls of those he decapitated. His 14th-century empire stretched from India to Istanbul.

Even by the standards of the Soviet Union, which swallowed up Uzbekistan wholesale in the 1920s, Timur's excesses were considered to be a little too brutal.

Airbrushed out of history in favour of the hammer and sickle, the monstrous emir took his time, but eventually – and almost inevitably – returned to prominence as a
de facto national hero.

After the collapse of the Soviet Union in 1991, Uzbekistan, along with the four other 'Stan nations of Central Asia, all declared their independence and set about dismantling the statues of Lenin and Marx that stood inert over parks and squares that now rumbled to the sound of pop music rather than parades.

It also meant that the piecemeal renovations of the madrasas (religious schools), mosques, caravan stops, markets, bazaars and minarets scattered along the course of the Silk Road route came to an end.

The peak of this trade artery between Asia and the West was reached between the eighth and 14th centuries. Yet the romantic legacy of the route – where silks, jewels, furs, carpets and horses were shunted between distances as far apart as Peking and Paris – remained for long after.

Come the 1990s however, funds from Moscow were no longer available to restore the architectural behemoths that marked the journey. The future hadn't seemed this uncertain since the fractured, dissolute rule of Timur's sons and grandsons following the death of the bearded tyrant.

A quarter of a century on from the post-USSR creation of the five independent 'Stan nations and the obscurity still remains almost total. Uzbekistan, shaped like a snapping dog and buried in the middle of the vast land mass is, apart from Liechtenstein, the only double land-locked country on earth. This means that, from here, you'd have to travel across two nations to get within hearing distance of any sea or ocean.

It goes some way to explaining why there's not much in the way of piscine pleasures for sale at the immense Chorsu market in central Tashkent, the sprawling Uzbek capital that retains its epic communist dimensions of wide boulevards and concrete hotels, but has also added a splash of designer outlets and upscale burger bars. Borscht and bling coalesce here and they both thrive in equal measure.

The Silk Road Express, the supremely comfy private train I'm travelling on, makes a four-times-yearly journey through Uzbekistan, Turkmenistan and Kazakhstan.

The goods being traded along the silk road may no longer inspire, but the temples, minarets and mosques remain

Taking 14 days, the train lurches to a stop at Tashkent one grey morning where, after a walk through the wide boulevards and milk carton-shaped apartment blocks, I look up at the immense dome which houses the meat market section of Chorsu.

Like something straight out of a Stanley Kubrick movie set, this immense piece of Soviet space-age design is ringed by concentric circles of vendors selling everything from khasyp – sheep's intestine stuffed with lungs and rice – to horse sausage and bulging pies made with lamb meat and lard from the sheep's rump.

A man attempts to sell me a live chicken for eight euros. His persistence is admirable and he certainly has more fighting spirit than the chicken, which looks a particularly depressed specimen. Yet I felt that the true mercantile greatness of the Silk Road lay beyond this most offal-y outré of markets.

Uzbekistan was once the heart of this ancient trading route. Caravan cities are still scattered along the dusty southern borders of the nation where – in centuries past – honey, amber and fur travelled east and jewellery, jade and, obviously, silk travelled west, strapped onto camels whose endless plodding helped to create one of the world's most efficient early versions of Amazon Prime.

In Bukhara, however, my penultimate stop before Samarkand, I observed that the huge 'tak' trading domes where merchants would sell wares ranging from saffron and silk to sugar were now populated by bored-looking locals with trestle tables full of bottled water, fridge magnets and very cheap plates. The goods on offer in such a grandiose environment looked horribly unworthy – like replacing all the paintings in the Louvre with postcards of Justin Bieber.

A group of backgammon-playing men sipping tea under a mulberry tree caught my attention. Their Uzbek was completely impenetrable to me but I caught one word being used over and over again in an increasingly hyperbolic fashion: 'Karimov'.

Central Asian states still love a 'big man' leader. Turkmenistan endured a decade under Niyazov, a man who named the months of the year after members of his family and banned beards, ballet and bears from his nation. Uzbekistan didn't quite manage this level of insanity, yet under the rule of Islam Karimov – who died in 2016 – the nation developed a basket case reputation for corruption and for intimidation towards dissidents; the BBC is banned and there are more than 30 journalists who are currently in jails around the country for crimes including 'insulting the dignity of citizens'.

Current president Shavkat Mirziyoyev doesn't seem to go in for portraits of his face emblazoned on walls around Tashkent. This is a city that, in its immaculate lawns and boho cafés, has exactly the kind of metropolitan panache that you would expect from a city that was once the fourth biggest in the ex-Soviet Union.

Yet sheep's lungs and fridge magnets can only satisfy for so long. The goods being traded along the Silk Road these days may not excite but the temples, minarets and mosques remain. And nowhere do they dazzle more than Samarkand.

Registan Square, in the centre of the city, was the kind of fantastical, almost mythical place that inspired the likes of Keats and Goethe to wax lyrical. Deep blue and green tiles on the domes, complex geometric patterns and quotations from the Koran, swirls and splashes of tiles whirling around the high central arches to create friezes that still exude brilliant explosions of iridescent colour.

From a distance it appears that the buildings operatically echo each other, all covered with the most intricate of tattoos. It is deeply, wholly beautiful and the ultimate expression of Timur's legacy, built to honour the fearsome ruler who once stated: "If you have doubts in our might and power – look at our monuments".

Minarets, shaped like giant pepper grinders, gently lean at slight angles to the sides of the three central madrasas on the square due to past earthquakes. Walking into the inner courtyard I find acres of carved gypsum on the walls of throne rooms that ripple like sheets, nibbled and chiselled with a precise mania.

The sun beats down on the almost-empty courtyard. Tourism here is still very much in its infancy, not helped by the brief spring and autumn seasons in which the temperatures are tolerable to outsiders. Come June and July it can hit a thermometer-shattering 50 degrees in Samarkand.

the geometric patterns of silk rugs seem to almost shimmer in hues of indigo and crimson

Finally, here I found totems of value. One bearded gentleman presided over innumerable sacks of saffron, basil, mint and cinnamon. Women with Hogarthian faces stood inert over immense rugs and carpets made from sheep's wool, camel wool or silk. Uzbek silk is still considered to be the finest in the world and the geometric patterns of the silk rugs seem to almost shimmer in hues of crimson, indigo and yellow.

One man, with a bulbous nose and a small round cup of scalding tea in his hand, invites me to take a look at his collection of knives. The wide, glinting, carbon steel blades are ground from one side, and kept in a straight leather sheath, the handles made from bone, wood and gemstones.

It seemed the perfect manifestation of the Silk Road's legacy; an item that's simultaneously desirable, useful, practical and extremely dangerous in the wrong hands.

"Most people have them but we usually use them to cut vegetables," he tells me as the sunshine gleams off the blades and seems to bounce onto the ancient, polished stone floors of the courtyard.

"It's good to have something to protect yourself though. This nation may well be modern now. But there's definitely a little bit of Timur in all of us still…"

To book the Silk Road Express luxury train's 14-day trip through Uzbekistan, Kazakhstan and Turkmenistan, go to trains-and-cruises.com. Prices from £2,447. Turkish Airlines flies from Heathrow to Almaty, Kazakhstan and Ashgabat, Turkmenistan via Istanbul. See turkishairlines.com