Ethiopia's monastic highs - Telegraph Although this was my first visit to Debra Damo, I already felt some acquaintance with the monastery. This is because my maternal grandfather, Derek Matthews, who was an architect, lived among the monks here for several months while he restored the larger of the religious community's two churches in the late 1940s. This crumbling structure has been used continuously for Christian worship since it was built, probably during the sixth century AD. My grandfather, who died in 2009, described it as "one of the oldest buildings in the world still in use." As a child, I often heard about his time there, and imagined him as a nimble 28 year-old, hurtling up and down the leather rope with the sure-footed alacrity of a vervet monkey. At the end of last year, I decided to visit it for myself. Ensuring the survival of the church at Debra Damo was my grandfather's first job as a qualified architect. He was already familiar with East Africa thanks to his experiences during the Second World War, when he helped to liberate Ethiopia from Italian occupation in 1941. In the same year, gunshot shattered his left elbow and crippled his left leg. After six weeks in a hospital in Alexandria, he was invalided out of the Army, and retrained at the Bartlett School of Architecture. While he was studying, a British entomologist and pioneering architectural historian, David Buxton, visited Debra Damo in 1944. Lamenting the ruinous state of the monastery's famous church, Buxton wrote to Haile Selassie recommending it be restor ed. (The church is dedicated to Abuna Za-Mika'el Aregawi, one of the so-called "Nine Saints" who spread Christianity through the ancient Aksumite kingdom in what is now northern Ethiopia in the fifth or sixth centur y AD. According to tradition, Abuna Aregawi founded the monastery after he was safely dropped on top of the mountain by a serpent.) The Ethiopian emperor petitioned the British government, and upon the recommendation of the prominent architect Albert Richardson, who taught at the Bartlett, my grandfather was offered the job. It was a prestigious commission. According to David Phillipson, author of Ancient Churches of Ethiopia (2009): "Debra Damo is a truly remarkable place. Its subsequent development has seen a great deal of rebuilding, but the basic form of the large church originates from the sixth century. Elsewhere in the world the great majority of churches built in that period are either in ruins or incorporated into later structures, or have disappeared altogether. The decoration of Debra Damo provided the prototype for the famous 13th-century monolithic rock-hewn churches at Lalibela in northern Ethiopia. My grandfather flew to Addis Ababa via Cairo at the end of 1947, having proposed to my grandmother that summer. To begin with, he covered 5,700 miles by lorry and mule in Ethiopia and Eritrea, gathering materials and workmen. The following Valentine's Day, with thunder echoing in the distance, he arrived at Debra Damo for the first time and ascended the rope. "The church compound was packed with monks in gorgeous robes," he wrote a decade later. The silence was intense, until the musicians started their wild chanting, punctuated by irregular drum beats. After establishing himself in one of the monastery's houses, where he used to drink "excellent" honey wine and home-brewed beer, my grandfather inspected the two-storey church, which was close to collapse. The external walls bulged outwards, "mushroom-like." The flat earth roof had partially collapsed. With the help of a local foreman, whom he described as "a genial rogue wearing a leather skirt," my grandfather began the complex task of restoration. Building materials, including cement bags, which had been carried by mule from Asmara in Eritrea, as well as reinforcing rods, sand, stone and scaffolding poles, had to be hauled up the cliff. Two reinforced concrete beams were placed within the thickness of the church's walls, "encircling the building like belts." "He took the greater part of the building down piece by piece and reassembled it meticulously," says Phillipson. In this he was way ahead of his time. After 82 working days, the restoration was finished. On arriving at Debra Damo, I was eager to ascertain the condition of the church. First, though, a 25-year-old trainee monk called Lsene (below), whom I had met by chance in the gatehouse, gave me a tour of the rest of the monastery. In 1948, Debra Damo was home to 300 monks. Today around 130 live on the summit, a grassy plateau studded with olive and eucalyptus trees that stretches for 650 yards from north-east to south-west, and is about 200 yards wide. Women are forbidden from entering the monastery. So too are the animals the monks pen in two small walled enclosures and kill on feast days: only oxen and rams graze on the summit, while roosters peck in the dirt, presumably dreaming about harems of hens. This results in frustration: I noticed skinny rams attempting to mount each other before butting heads with a vicious thunk. I was less certain that the wild grey monkeys springing about on the hilltop were abiding by the monastery's strict rule. Lsene led me through a labyrinth of tumbledown dwellings to his quarters - a spartan hall that he shares with nine other students. Most of his belongings, including his bedding, were stuffed inside a yellow plastic bag emblazoned with the crest of Manchester United. "Yes, I support them," he said, though he did not know where - or what - Manchester was. As the sun was setting, and plump hyraxes played on the grass, we followed a path beneath the summit's south-west lip, and peered inside tiny caves containing human skeletons - the remains of monks who, in centuries gone by, gradually wasted away while meditating on the magnificent vista of tangled mountains and gorges before them. "I couldn't imagine doing that myself," Lsene told me. The monks eat together twice a day. "During the rainy season we plant salad and spinach and sell it to buy plastic shoes and trousers," Lsene said. On our way to dinner, we passed deep rock-hewn cisterns. During the rainy season these fill with enough water to supply the community throughout the year. The water in each cistern was covered with a thick green weed. Although my grandfather "suffered no ill effects" from drinking this, I decided to stick to the bottled water I had brought with me. Over dinner, I asked the monks whether they had heard of him. "Yes," one said. We know that the church was falling down and a faranji [foreigner] came to repair it, reinforcing it with concrete. As we ate injera, a staple carbohydrate like a large pancake made from a nutritious grain called tef that is unique to Ethiopia, I looked at the poster of a city full of futuristic skyscrapers with which our young host had decorated his digs. Compared with the simplicity of Debra Damo, it seemed like a vision of another planet - until, after we had finished eating, several monks began playing games on mobile phones. That night, Lsene woke me at 3am to take me to a service in the large church. It was the first time I had seen this wonderfully wonky structure up close. Nothing about it is angular or straight: every element is worn, weather-beaten and askew. The crooked walls consist of tile-like stones set in earth mortar and strengthened with bands of longitudinal timber beams, which give the building a layered look incongruously reminiscent of a Swiss chalet. The domed ends of smaller supporting beams projecting outwards from the external walls are known as "monkey heads." The only significant change since my grandfather's visit has been the addition of a red, corrugated metal roof. Near the church, the tart night air was sweetened by frankincense. Aside from bewitching wind chimes, and the occasional hoot of an owl, all I could hear was the soft chanting of the monks, accompanied by deep-throated drums and sistra - hand-held musical instruments that jangle like a Morris dancer's bells. The monks had been chanting since midnight, and would continue until it was light. As I looked up at the star-bright sky, which appeared more luminous and less remote than ever before, I recalled the words of my guide anticipating our visit two days earlier: "It's beautiful up there at Debra Damo - as close to heaven as you can be." Alastair Sooke was a guest of Wild Frontiers (020 7736 3968; wildfrontiers.co.uk), which offers small-group tours and tailor-made holidays to Ethiopia. Prices for a 10-day trip start at £1,495 per person, excluding international flights. The company can also organise these, from about £650 return. Any male tourist can visit Debra Damo for a fee of about 200 Ethiopian birr (£7). Notice isn't required, though the site becomes busy in October, when Ethiopians converge on the monastery to celebrate its foundation. It is possible to stay the night, but accommodation is basic. Axum, Lalibela and Gondar Using the efficient Ethiopian Airlines, I was able to take in a few other sights, including Axum, Lalibela and Gondar. The ancient kingdom of Axum, which once exerted influence from the Sudanese Nile Valley to southern Arabia, deserves to be as familiar as the civilisations of Egypt, Persia, Greece and Rome. The main archaeological attraction is the stelae field in the centre of town. Its largest monolithic obelisk - a 510-ton leviathan once 100ft high but now flat on its back - was the largest single standing stone in the world. The monolithic churches hewn out of rock a millennium or so later high in the mountains at Lalibela, 150 miles to the south of Axum, are similarly awe-inspiring. The tourism infrastructure in Lalibela can feel oppressively advanced, but this has advantages: I stayed in the Mountain View Hotel (mountainsviewhotel.com), which was superb. Gondar (above), the 17th-century stronghold known as Africa's Camelot, can be seen in a day. Tigray trek Aside from staying at Debra Damo, my favourite part of the trip was a two-night trek through the northern highlands of Tigray. Organised by Tesfa Tours (tesfatours.com), it involved scrambling up rickety ladders to visit remote rock churches, and walking between villages, where we stayed in compounds that had been built and were serviced by locals. The spartan guesthouses will not be to everyone's taste, but the welcome I received from villagers, who receive a proportion of the nightly rate of around £35 per person, in addition to tips, was delightful - and the sense of getting away from the usual destinations was intoxicating. Visas/vaccinations A tourist visa is required to enter Ethiopia, but it can be issued for $20 on arrival at Addis Ababa. Make sure you bring a couple of passport photographs to complete the application. For latest health advice, see nathnac.org. What to read Ethiopia Highlights (Bradt).