Even by the placid standards of its species, it was a relaxed sheep, It made no attempt to move when I tried to squeeze by in the narrow, stony lane.

And then I saw the reason. It was munching discarded khat leaves - and why not?

It seemed most of the population of Harar that hot Sunday afternoon was chewing khat, the mildly narcotic shrub, the leaves of which are widely and legally consumed in Ethiopia, Yemen, Somalia and other countries in the area.

Individually or in groups, men and women, sat or sprawled, have bunches of young leaves to hand.

They let the drug perform its work of inducing well-being, a sensation of deep insight and optimism - and then insomnia and depression.

To get to Harar you go to the Ethiopian capital Addis Ababa, drive 500km (300 miles) across some pretty desolate country to a grim railway town called Dire Dawa, where the young Evelyn Waugh came close to dying of boredom in the 1930s.

Another 50km on (30 miles), you pass a customs post where they collect the taxes on khat and try to catch goods smuggled in from neighbouring states.

You then arrive at Harar, as exotic and improbable a destination as you will find.

This old walled city is overwhelmingly Muslim. It was a powerful and independent emirate until the late 19th Century, and birthplace of Ethiopia's last emperor, Haile Selassie.

Keeping house

It is almost a caricature of the romantic idea of a mysterious city of exotic Araby, with its 380 narrow twisting lanes and alleys and more than 80 mosques.

Doors set into walls painted white, green and blue open on to the spacious courtyards of traditional houses.

A carpet over the door indicates the presence of a marriageable daughter

In their cool interiors, traditional pottery and exquisite baskets crowd the walls, side by side with crude, modern Chinese enamel basins and plates.

The floor in the main room has different levels on which people sit in accordance with their status.

A carpet over the door indicates the presence of a marriageable daughter.

Honeymoon couples are confined to one small adjoining room for a week. Food is passed in through a window, though one assumes the happy pair is allowed out for natural reasons from time to time.

At night the hyenas - three, six, 10, then a dozen - slink out of the shadows to one of the gates to be fed goats' entrails.

If tourists are there, the show will be enhanced a little, but it takes place whether goggling "faranji" - foreigners - are present or not.

Identity

Only one of Harar's streets is wide enough to drive a car

The city is physically many hundreds of dusty kilometres from the extraordinary rock-carved churches and dim-lit monasteries of the fiercely Christian north, hypnotised by ritual and the shape of the cross, and culturally it is similarly removed.

It is asserted - on what evidence I cannot discover - that Harar is Islam's fourth holiest site, though unlike Mecca, it has a Czech-built brewery producing excellent alcoholic and non-alcoholic beer.

The presence of the brewery and of a mineral water factory are the stranger, inasmuch as the city suffers from a chronic water shortage.

When we were there, local people had to form long queues with their yellow 20 litre jerry cans to fill up from tankers.

Rich culture

But back to the khat. Of course I tried it, but it made me thirsty and I had neither the time nor the patience to chew for the several hours necessary to fully appreciate this type of lotus-eating.

I would have missed the parade of the newlyweds in western dress, driving round the town square and up and down the single street that cars can negotiate.

Facts about khat It is a natural stimulant from the Catha Edulis plant Khat is legal in Britain but banned in Europe, America and Canada Effects include euphoria, extreme talkativeness, and inane laughing Side effects can include dizziness, heart problems and anxiety Other names include Qat, Chat, Kat, Abyssinian Tea, mirraa and African Salad

I would have missed seeing the museum devoted to the marvellous boy, the French prodigy poet Arthur Rimbaud who, after abandoning his muse at the age of 19, fetched up in Harar and eventually embarked on a singularly unsuccessful career as an arms dealer in the region.

I would have missed the smuggler's market, where goods driven in across the desert from Djibouti and Somalia are openly traded.

I would have missed the Italian fascist-era architecture in the new town.

I would have missed the recycling market where everything from old tyres to cooking oil tins is converted into something useful.

I would have missed buying the explosive local spices.

Way of life

The local passion for khat has a price. The bunch I bought - and was surely overcharged for - amounted to a day's average earnings.

The country's roads are lined with wrecked vehicles, whose drivers chewed the leaf to stay awake but lost concentration.

It is socially disruptive.

Khat is more popular than coffee beans among Ethiopian farmers

Ethiopia is deservedly famous for its coffee, but farmers are tearing up their bushes - understandably given the collapse in coffee prices - in favour of the much more easily grown and profitable khat shrub.

Khat is now a major source of government revenue and export earnings.

It is Sunday afternoon in Harar and on a corner, a building with boarded windows offers access by ticket only.

From inside float the flat familiar live tones of Britain's leading football commentator: "a little unlucky to get that yellow card," he opines.

Outside women in traditional dress, importunate children in rags, youths in t-shirts bearing western slogans squeeze along the alleys.

On the rooftops the hawks wait for scraps of meat from the market.

Women who may have walked for hours along mountain roads offer firewood for sale for pennies. And in the corners in the shade people munch in companionable silence.

There is not much chat, when khat is chewed.