Frankfurt Airport inaugurated its long-awaited fourth runway on Friday, amid protests by conservationists and local residents and a bitter row over night flights at Europe\'s third-biggest airport. Chancellor Angela Merkel was the first to use the 2.8-kilometre (1.7-mile) landings-only strip, which has taken 14 years to build at a cost of 600 million euros ($833 million), touching down in the government\'s Airbus at 2:30 pm (1230 GMT). She was welcomed by the local state premier of Hesse, Volker Bouffier, Frankfurt\'s mayor Petra Roth, as well as the head of airport operator Fraport, Stefan Schulte, and Lufthansa chief executive Christoph Franz. Amid loud whistling and jeering outside from protesters, Merkel insisted the new runway, one of Germany\'s biggest infrastructure projects in recent years, would benefit not only the airport, but also the region and Germany as a whole. \"It is an expression of the future sustainability of Germany as an economic location,\" she said. Frankfurt airport, one of the most important air hubs in Europe and a key engine of growth, was of crucial importance for Germany as an export nation, Merkel said. Hesse state premier Bouffier said that while the mammoth project had been beset by controversy, building an additional runway was \"important and necessary\" since it would create wealth and secure employment in the region. But he conceded that it would also represent an additional burden for local residents in terms of noise and pollution. The new runaway was first proposed in 1997, but construction only began in 2009. Airport operator Fraport argues the runway is essential if Frankfurt is to keep pace with London\'s Heathrow and Paris\'s Charles de Gaulle. According to Fraport, Frankfurt, which handled 53 million passengers and 2.2 million tonnes of freight last year, has been operating at the limits of its capacity for years. Until now the airport has had a maximum capacity of 82 take-offs and landings per hour. Once the expansion is complete, it will be able to handle 126 per hour, or 700,000 per year. Nevertheless, the new runway has been overshadowed by a decision by a German court last week to slap an injunction on take-offs and landings between 11:00 pm and 5:00 am until a dispute between local residents and airport operator Fraport can be decided by a federal court next year. The decision has enraged airlines, not least German carrier Lufthansa whose freight unit Lufthansa Cargo is dependent on night flights. \"Freight needs the nights,\" raged Lufthansa chief Christoph Franz, describing the court ruling as a \"heavy blow\" not only to his company but Germany as a whole. As a result of the injunction, Lufthansa Cargo is having to reroute its flights to the Cologne/Bonn airport, which was \"economically and ecologically grotesque\", Franz said.