Overlapping sovereignty claims in the Arctic are being increasingly supported by more robust military presences in the High North. The listed bases are all those either within the Arctic Circle (above 66°33' North) or close to it. Two (Resolute Bay and Nanisivik in Canada) are currently under construction. Keflavik International Airport is no longer a NATO base, but NATO aircraft tasked with maintaining Iceland's air sovereignty utilise the facilities. Minimum sea ice extents are included to demonstrate how retreating sea ice is making two potential Arctic transport routes more accessible. Although the minimum extent in 2011 was greater than the record low of 2007, the trend has been consistently downward for the past few decades.