The Mainland, Orkney shown within The Orkney Islands

The Mainland is the main island of Orkney, Scotland. Both of Orkney's burghs, Kirkwall and Stromness, lie on the island, which is also the heart of Orkney's ferry and air connections. The island is relatively densely populated and has much fertile farmland.

The bulk of The Mainland is west of Kirkwall. It is low-lying, but with coastal cliffs to the north and west and two sizeable lochs. This western section of the island contains numerous Neolithic and Pictish constructions.

The eastern part of The Mainland is shaped like the letter "W", the easternmost peninsula being known as Deerness. To the south, causeways connect the island to Burray and South Ronaldsay via Lamb Holm and Glims Holm.

The following parishes are on The Mainland:

• Birsay
• Evie
• Sandwick
• Harray
• Rendall
• Stromness Parish
• Parish of Firth
• Orphir
• St Ola
• Parish of St Andrews
• Holm
• Deerness