Some 2,000 years after they were first erected, Ancient Roman harbors made from concrete are still standing across Europe. Meanwhile, more modern constructions have proved far less durable. Finally, scientists have solved the puzzle of what made the ancient concrete so strong — and they think the discovery could make modern buildings more environmentally friendly. The results are published in American Mineralogist. Concrete used for ancient sea walls was made by mixing lime, seawater, volcanic ash and rock. Researchers have now discovered that elements in the ash react with sea water, which actually strengthens the material. Researchers discovered the Roman concrete contained aluminium tobermorite, a rare mineral that adds extra strength. When the Roman concrete was exposed to seawater, the tobermorite crystallised and spread. The researchers said that long-term exposure to sea water helped these crystals to continue growing, reinforcing the concrete and preventing cracks from developing.

Italy has earmarked over US$ 20 million to rebuild the arena floor in the Colosseum where gladiators once fought wild beasts, Culture Minister Dario Franceschini announced. The idea is that the arena could be used once more to house events and perhaps even re-enactments of spectacular Roman-era shows, while the area below where the beasts, scenery and props were kept would be turned into a museum. The planned arena reconstruction will not affect 48-meters high Colosseum walls, which continue to break down. The biggest amphitheater built during the Roman Empire, the Colosseum stands 48.5 meters high. In Rome times, up to 80 thousand spectators would throng there to see gladiator greats such as Carpophores -- who reportedly defeated a bear, lion, leopard and rhinoceros in one battle -- or cheer on mock sea battles held in the flooded arena. It now welcomes over six million visitors a year. Besides the Italian Government, in Colosseum restoration are engaged also philanthropists. Long-delayed repairs, funded to the tune of US$ 27.8 million by Italian billionaire Diego Della Valle, began in 2013 and are expected to be finished in early 2016. The Colosseum undertaking is just one of the country's US$ 89 million cultural maintenance projects, which includes US$ 20 million to update the Uffizi Gallery in Florence, $7.7 million to update Turin's Polo Reale museum, and $5.5 million to expedite the progress of Pisa's forthcoming museum of ancient ships.

As anyone who's ever visited Italy knows, the ancient Romans were master engineers. Their roads, aqueducts, and temples are still holding up remarkably well despite coming under siege over the centuries by waves of sacking marauders, mobs of tourists, and the occasional earthquake. But it seems the Romans also knew a thing or two about making concrete. While world's 1960s concrete tower blocks and flyovers are crumbling, Roman monuments such as the Pantheon and the Coliseum are still standing. Now scientists have discovered the secret ingredient behind the longevity of Roman concrete - volcanic ash. The study by the University of California, in Berkeley, found Roman concrete showed no corrosion, with a smooth surface suggesting long-term stability. Manufacturing modern cement requires heating a mix of limestone and clay at 1,450C. But Roman architectural mortar uses 85 per cent volcanic ash, fresh water and lime, which is cast at a much lower temperature, significantly reducing its carbon footprint. Now the researchers want to take the Roman techniques and apply them to modern cements. Dr Marie Jackson said: 'If we can find ways to incorporate a substantial component of volcanic rock in the production of specialty concretes, we could greatly reduce the carbon emissions associated with their production. We could also improve their durability and mechanical resistance over time.'

The ancient Coliseum of Rome, where gladiators fought for their lives, is slanting about 40 centimeters lower on the south side than on the north, and authorities are investigating the project for urgent repairs. The Coliseum has been in need of restoration for years. Last year chunks of masonry and stone have regularly fallen from the arena. Authorities became aware of the tilt in the 2000-year-old amphitheatre about a year ago and have been monitoring it closely for the past couple of months. They believe that "dynamic vibrations" caused by Rome's heavy traffic, may be responsible for the drop on the south side next to one of Rome's busiest thoroughfares. Experts from Rome's Sapienza University and the Institute of Environmental Geology and Geoengineering (IGAG) conducted an urgent scientific study to determine the cause. Professor Giorgio Monti, from Sapienza's department of structural engineering, said he fears there may be a crack in the base of the monument. "The concrete (Roman Cement) foundation on which the Colosseum is built is an oval-shaped 'doughnut' which is about 13 meters thick," ProfMonti said. "There could be a stress fracture inside it." On July 31 Lorenzo Ornaghi, Italy's culture minister, unveiled the timetable for the controversial restoration, flanked by Gianni Alemanno, the mayor of Rome, and Diego Della Valle, the billionaire businessman footing the bill, reported the Telegraph. In the first stage of the project, four floors of scaffolding are expected to cover the monument's arches for a total of 915 days - two-and-a-half years - as the ancient amphitheatre's facade and entrances are rebuilt. Culture officials however stressed the monument would remain open to the public during construction. The new project will also look at the "dynamic vibrations" that officials fear have caused a drop of up to 15 inches on the south side of the monument, although as yet there are no plans to address the list. The restoration also provides for the construction of a tourist service centre outside the monument, while the third phase includes restoration of the internal area and a more comprehensive restoration of the underground cells or hypogeum beneath the arena. The restoration works have been delayed by a series of protests by trade unionists over Italian tycoon Diego Della Valle's plans to clean up the dirt-streaked arena. In January, the billionaire threatened to pull US$ 32 million in financing following investigations into alleged irregularities. The three-year restoration project, which aims to increase by a quarter the areas to which tourists will have access, was supposed to begin in March. It was postponed to July and is now unlikely to start before the end of the year. Designed as a 50 thousand seat amphitheatre and completed in 80 AD under the Emperor Titus, the Colosseum was used for gladiator contests and mock sea battles. It is considered one of the masterpieces of Roman architecture. The number of visitors to the site has gone from around one million visitors a year to around six million annually over the past decade. The Leaning Tower of Pisa, another popular Itaian attraction was reopened last year after being shut for a long time as engineers worked to prevent it from falling over and to make it safe for visitors.

As reported by france24.com, St. Peter's Square will be restored to its 17th-century Baroque glory with a major renovation project due to be completed in 30 months. Work has already begun on part of the famous colonnade designed by Gian Lorenzo Bernini (1598-1680) - the sculptor and architect behind some of Rome's best-known landmarks. It will restore the colours and the architectural integrity of Bernini's original design said the head of Vatican technical services, Pier Carlo Cuscianna. The project will encompass all of the square's 376 columns and pillars, 140 statues and 1,200 meter in terraces and cornices, as well as the Clementina and Gregoriana fountains and the Egyptian obelisk in the middle. "Generous sponsors" are financing the project, Cuscianna said, without mentioning any names. The Vatican Museums will oversee the work and two Italian companies Italiana Costruzioni and Fratelli Navarra have been selected to carry it out.