Khalil Abdullah is the king of the castle – and the enemy is at his gates. The castle in question is the Village Chateau Wazzani Touristique; the enemy, 30ft across the brown-flowing stream, is the entire Israeli army in Israeli-occupied Golan. Indeed, two Israeli tanks turned up two weeks ago, their guns pointing menacingly towards Khalil Abdullah's 60ft palm-roofed Africa-style barn-restaurant, his castellated walls, his wooden drawbridge and his windmill-topped entrance towers. The Lebanese army have a sentry box above what will be the swimming pool and United Nations troops of the German and Belgian battalions drop by twice a day to make sure the world has not gone to war over Mr Abdullah's 40,000sq m hotel-to-be.

Yes, a theme-park hotel is what this extraordinary man is doing with the £2m he saved while working for 40 years in the construction business in West Africa. The "African" barn is the inspiration of his years in the Ivory Coast city, Abidjan. The windmills on the gate remind him of his grandfather, who owned a real windmill – long destroyed – on the spit of land where the Wazzani gently drifts between Israel's illegally annexed Golan Heights and the Republic of Lebanon and the border of Israel, which Mr Abdullah, a Shia Muslim, patriotically refers to as "Palestine".

It took me 15 minutes before I put the question on everyone's lips: isn't Khalil Abdullah absolutely and completely, certifiably mad? "That's what people tell me," he replies. "But it's my land and I have the right to live on it and build on it and no one has the right to throw me out. It is perfectly safe here, no Israeli cluster bombs fell here in the 2006 war; because of the waters of the Wazzani, it is in the interest of both the Israelis and the Hizbollah to leave it alone."

He has a point: for this beautiful little watercourse trickles out of the earth only a mile and a half to the north, inside Lebanon, and trickles equally nonchalantly under the Lebanese border fence on the other side of the site into the land that Khalil Abdullah refuses to call Israel.

A trip round the Chateau Wazzani Touristique is a journey into Lebanon's furthest fantasy. Massive stone piles are ready for two huge waterfalls. There's an artificial island – built, of course, by the king of the castle – with a real tree planted on it; there seems to be some doubt if this is in occupied Syria or in Lebanon because Khalil Abdullah claims, in rather unlikely fashion, that Syria – and now occupied – Golan starts on the far bank. Old French maps suggest the frontier runs down the centre of the river and might cut the island – uncreated when the post-First World War French mandate took possession of Lebanon and Syria – in two. This might be why, according to the hotelier, 13 Israeli soldiers crossed the stream before dawn a few days ago, stole – so he says – the steering gear of his tractor, and, once dawn was up, snapped pictures of his extraordinary project.

"This is an Arabic Byzantine-style castle," announces this most ambitious of all Lebanese men, waving his arm towards the ramparts above a series of soon-to-be-finished chalets. "It's Arab Maghrebian inside, North African so that our guests will feel they are international."

And that's what he expects his clientele to be, international tourists looking for a place to hide away with no sound of traffic and only storks and eagles to keep them company – apart from Israeli Merkava tanks, a Lebanese personnel carrier and visitors from two of the UN's Nato armoured brigades. The UN's notoriously inaccurate "Blue Line" – the creation of an equally ambitious UN bureaucrat who wanted to divide Israeli and Lebanese forces – wanders somewhere near here. No one will say where.

Khalil Abdullah scurries to the hillside, jumps into a 4x4, and skids up an earth track to the foundations of two dozen more chalets. This time the view is breathtaking: to the east and north, Shebaa Farms (Lebanese, in fact, but occupied by Israel inside the Syrian Golan); the wide, damp, soft vale of Galilee in old "Palestine" and present-day Israel to the south; and the mountains of Lebanon upon which the old Crusader keep of Beaufort Castle – much smashed up in 25 years of war – still stands gloomily over the neighbouring Litani river. "In two months, we will be open for business," Khalil Abdullah announces, opening his notebook. "You can soon google us on www.hossonelwazzani.com, and right now on www.alintiqad.com, and you can give my mobile to anyone who wants to call: 00 96 1396 1496."

Mr Abdullah speaks good French as well as Arabic, but visitors are advised – by me – to check if there isn't another Hizbollah-Israeli war in Lebanon before making a booking. I can see the odd journalist turning up, and the nightclub set from Beirut arriving for a long weekend, just for the devil of it. Lebanese villagers are already arriving to gaze at the bottom of the 40ft swimming pool, the Wazzani waters as they flow between the "African" barn (which will be a massive restaurant), the castle walls and that highly political, artificial island.

Even the local Lebanese military intelligence boys drop by from time to time. And so, of course, do more secretive folk. "Yes, a few of the Hizbollah people came here, and they saw." Rumour has it that their interest was less strategic and more moral; it's said they don't want alcohol served in this tiny, last corner of Lebanon. Some hope. The Christians in neighbouring Khiam and in Maronite Marjayoun are not going to obey that kind of restriction.

Mr Abdullah also has a home south of Sidon but seems curiously ignorant of his own family background. His sister and three brothers are supporting the hotel project, but he doesn't know how his grandfather – who died "in 1946 or 1947" – got rich. "He owned vast lands all the way from here to Khiam and also in Palestine, which we lost, of course, in 1948. He was a landowner. I don't know how he made the money for the land."

There's one other thing. Across in the neighbouring Lebanese village of Shrifa a few days ago, a minor earthquake brought down several roofs. For the Chateau Wazzani Touristique lies on a geological as well as a political fault line. All that, and the Israelis, the Lebanese and the UN too. Readers need not doubt how I bade farewell to Khalil Abdullah yesterday: "GOOD LUCK!" I shouted, and didn't look back.