The Helgeland Bridge spans over the deep Leirfjord with a gentle arch, connecting the two municipalities Alstahaug and Leirfjord. The slanted metal cables that connect the tall vertical supporting towers and the more horizontal bridge deck, from a distance, appear reminiscent of e.g. a musical instrument or a sail.

The bridge is a stay cable bridge, in other words, a type of hanging bridge where the bridge deck is supported by cables suspended from the tall towers. In reality the cables are slanted stays which are suspended from the apex of the tower to the bridge deck. The bridge has a main arch measuring 425 metres. In total the bridge measures 1,065 metres in length. The towers have a modified diamond form and in height measure 127.5 and 138 metres respectively. The boat clearance under the bridge measures 43.5 metres in height. When the bridge was completed it was one of the longest stay cable bridges in the world.

The Helgeland Bridge provides Sandnessjøen with a connection to the mainland. This project was worked on over a period of several years and many different plans were proposed. In 1987 a final decision was approved to build the mainland connection for Sandnessjøen and the island Alstenøya over Skreingan - and the bridge was completed in 1991. It is a part of the Riksvei 17 (Classified Road 17) in Helgeland, which is also called Kystriksveien (Coastal Classified Road).