'This was seen as the Riviera of the Soviet Union,'’ said my guide, Datu, as we ventured deeper into the ornate corridors of Tskaltubo Spa Resort – a 137-room, four-star hotel in what is now Georgia, but formerly the exclusive sanatorium of Joseph Stalin’s Ministry of Defence. ‘When the Soviet Union was at its economic height in the Sixties and Seventies, the resort prospered,’ Datu went on. ‘There were cinemas, theatres, ballrooms and sports teams. People would come here on holiday from all over the USSR.’

Spread across 1,600 acres of boulevards, parks and ponds, the city was renowned for its healing mineral waters and radon bath treatments. At its peak there were 22 sanatoriums with 5,800 bedrooms, plus nine bathhouses hosting 1,500 spa guests every day. So popular was it, a grand train station was built to welcome holidaymakers arriving on a direct two-day service from Moscow. But as the Soviet Union began to crumble, so too did Tskaltubo’s extravagant infrastructure – and 28 years on from Georgia’s independence, most of the city’s palatial buildings lie in captivating ruin. Long grass shrouds the train station’s steel tracks – and inside the departure hall, tiny specks of ceiling mosaic rest in dusty puddles.

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There are around 25 basic hotels and hostels in the city, but Tskaltubo Spa Resort is the only one housed in a former sanatorium. It’s particularly popular among the Kazakh, Polish and Azerbaijani tour groups that these days visit the city’s four bathhouses.

Partially submerged spine-stretching treatments, Botox injections and minor plastic surgery procedures are in vogue, alongside the timeless appeal of mooching around in plunge pools filled with water at 35C. At ‘‘Bathhouse Number 6’’ there is a chance to soak in Stalin’s private spring – though it’s uncertain whether he ever used it.

Part zombie apocalypse movie set, part out-of-season Center Parcs, the city has a surreal ‘‘end of days’’ atmosphere akin to Chernobyl, Fukushima or Pyramiden. Weirder still, Tskaltubo has become popular among wedding parties and is used as a lavish, albeit spooky, backdrop before which brides and grooms pose for photographs beneath ostentatious arches and gaudy faux-Roman columns.

On the Tuesday I visited, there were four weddings – and according to the local tourist office, the city attracts several hundred a year. ‘Once we had 14 in a single day,’ I was told by Nino, a local tour operator and lifelong Tskaltubo resident. ‘All the sanatoriums are public spaces – so it’s free.’

The Georgian government hopes to return Tskaltubo to its former glories, and a master plan was conceived in 2013 to attract national and foreign investors. Since then, the World Bank has helped fund the regeneration of the central park, lakes and roads – and six of the city’s sanatoriums are now privately owned and awaiting redevelopment.

But there remains a much more pressing issue – what to do with the thousands of internally displaced people (IDPs) who have lived in Tskaltubo’s 14 abandoned hotels for more than 25 years. The ruins were used to house refugees fleeing the 13-month Georgia-Abkhazia conflict in 1992 and 1993. And while 1,759 families have been successfully relocated to new apartments, 920 families continue to live in the crumbling hotel suites of former KGB officers, health workers and trade unionists.

‘Do you see tourists as voyeurs?’ I asked an old lady in the rundown sanatorium. ‘Is it bad that people come here and take photos?’

‘Even in times of great hardship, visitors will always be considered by Georgians as a gift from God,’ she said, as I was summoned into her room for a slice of cake. ‘I lost my daughter – she died at just 36. The sadness has never left me, but we have a strong community spirit here and it’s important people see this.

‘In the Nineties, we didn’t have any electricity, but now I have – so we must always take positives from life.’

The Daily Telegraph