Nigg Bay is a large, relatively shallow sandy bay, consisting of mudflats, saltmarsh and wet grassland, located on the north east coast of the Cromarty Firth, 5 miles (8 km) east of Invergordon, in the district of Ross and Cromarty and in the Scottish council area of Highland. At low tide, the Sands of Nigg are exposed. Nigg Bay can be said to start at Balintraid pier – probably the oldest pier on the Cromarty Firth – built by Thomas Telford in 1821. There is a wartime mining base alongside the pier and a series of coastal gun emplacements on the road to North Sutor.