Renewable energy in Scotland expensive to install, could be enough to provide almost half the total energy used in Scotland. Plans to harness up to 4.8 GW of the potential in the inner Moray Firth and Firth of Forth were announced in January 2010. Moray Offshore Renewables and SeaGreen Wind Energy were awarded development contracts by the Crown Estate as part of a UK-wide initiative. Also in 2010, discussions were held between the Scottish Government and Statoil of Norway with a view to developing a 5-turbine floating windfarm, possibly to be located off Fraserburgh. In July 2016, RSPB challenged development in the Firth of
Architecture of Scotland a line drawn between the Tyne and Solway Firth. Elginhaugh fort, in Midlothian, dates to about this period as may Castle Greg in West Lothian. The Romans eventually withdrew to a line in what is now northern England, building the fortification known as Hadrian's Wall from coast to coast. Around 141 A.D. the Romans undertook a reoccupation of southern Scotland, moving up to construct a new "limes" between the Firth of Forth and the Firth of Clyde. The Antonine Wall is the largest Roman construction inside Scotland. It is a sward-covered wall made of turf circa 7 metres (20 ft)