The contract for the protective shelters over Hagar Qim and Mnajdra Temples has been awarded to an Italian firm and works are expected to be completed by the end of 2008.

The total cost of the Hagar Qim and Mnajdra conservation and preservation project amounts to Lm1.8 million (excluding VAT). Just under two-thirds of it is being financed by the EU Regional Development Fund, under the 2004-2006 Structural Funds Programme, and the remaining by the government.

The contract for the protective shelters, the largest component of the project, is valued at just under Lm1 million. It has been awarded to Canobbio SpA - one of the longest-established companies in Europe in the business of tensile membrane structures - following a public call for tenders.

Meanwhile, work on the visitors centre, located in an unutilised area of the car park outside the entrance to the monument, has started, Reuben Grima, senior curator for World Heritage Sites, said.

The site was chosen to avoid any additional physical impact on the surrounding landscape. The centre will be spread over two floors and is to cover a floor area of 900 square metres. It will include an original interpretation area comprising an audio-visual and interactive experience, possibly just through a series of images, to prepare visitors to see the monuments. There will also be toilets, which, to date, are "embarrassingly" unavailable.

While the tent-like structures are being manufactured overseas and off site, it is envisaged that the monuments will be closed to the public at intervals between June 2007 and December 2008. Tour operators have been duly advised so as not to experience any problems, Mr Grima said.

Whatever the case, at any given time, at least two of the "big four" - Hagar Qim, Mnajdra, Ggantija and Tarxien - would be open to the public.

The purpose of the shelters is to protect the temples from the elements in the best way possible to date, while research continues on alternative and less visually intrusive ways to conserve them, Mr Grima added. The shelters have a lifetime of 25 to 30 years.

The decision to install them dates back to 2000, following an intensive study by a team of experts of the problems that threaten the megalithic monuments. They have been designed as a temporary measure, which is totally reversible and would have minimal impact on the ground, Mr Grima said.

While the fundamental concept has remained unchanged since the international competition in 2004, the design of the shelters has evolved slightly to have less of a visual impact.

They are being planned in the context of an ongoing environmental monitoring programme that will enable comparisons to be made between the situations before and after the installation. It has been shown that the temperatures of the stone can experience changes of 30°C in the space of a few hours every day - and more in winter.

The first phase of the monitoring programme, completed between 2005 and 2006, cost €159,000 and was funded by EU pre-accession funds. It is now being continued by Heritage Malta's Preservation Conservation Unit.

Since the temples were dug up, they have been vulnerable to the elements, particularly due to their exposed coastal location and because they are mostly built from soft Globigerina limestone. Rain, which washes away the soil that was used to fill the gaps between the stones, is another deteriorating factor, Mr Grima explained.

"Of course, it would be better to leave them uncovered, but the choice was between presenting the next generations with a somewhat reduced version of the temples, or taking on the responsibility and challenge of preserving them for the future so they can be enjoyed."

Heritage Malta chairman Mario Tabone stressed that the conservation and presentation project was of immense importance. It required intense behind-the-scenes scientific study to the highest standards, and preparatory work that the public would not be aware of.

Heritage Malta is also implementing another major project at the Tarxien Temples, heavily funded by Bank of Valletta, and is preparing for another substantial project at the Ggantija Temples. It is inviting theatre professionals to present proposals on how to use the quarry beyond Mnajdra theatrically.