page_title: Muskö naval base
hierarchical_section_title: Muskö naval base
caption_attribution_description: Svenska: I Muskötunneln, färdrikning mot Muskö
context_page_description: Muskö Naval Base is a Swedish underground naval facility on the island of Muskö just south of Stockholm in Haninge Municipality.
  The construction of the base started in 1950 and was completed 19 years later in 1969. During the construction about 1.5 million tons of rock were removed. It has 3 docks, originally designed for destroyers and submarines. The underground base itself has an area of several km² and is connected by 20 km of underground roads.
  In order to connect the base to the mainland, the Muskö road was built at the same time as the base. This crosses several bridges and intermediate islands before finally accessing the island of Muskö through the Muskö Tunnel, a 3 km long, dangerously narrow road tunnel running some 70 metres under the sea.
  During the Cold war the underground facility was kept highly secret and not much information about it was known to the public. In 2004 the Swedish government decided that the navy should be concentrated to two bases only, the Karlskrona Naval Base and the Berga Naval Base, and much of the Muskö base was closed. However some parts of the facility were still used by the military.
context_section_description: Muskö Naval Base is a Swedish underground naval facility on the island of Muskö just south of Stockholm in Haninge Municipality (Haninge Kommun).
  The construction of the base started in 1950 and was completed 19 years later in 1969. During the construction about 1.5 million tons of rock were removed. It has 3 docks, originally designed for destroyers and submarines. The underground base itself has an area of several km² and is connected by 20 km (12 mi) of underground roads. 
  In order to connect the base to the mainland, the Muskö road was built at the same time as the base. This crosses several bridges and intermediate islands before finally accessing the island of Muskö through the Muskö Tunnel, a 3 km (1.9 mi) long, dangerously narrow road tunnel running some 70 metres (230 ft) under the sea.
  During the Cold war the underground facility was kept highly secret and not much information about it was known to the public. In 2004 the Swedish government decided that the navy should be concentrated to two bases only, the Karlskrona Naval Base and the Berga Naval Base, and much of the Muskö base was closed. However some parts of the facility were still used by the military. The underground shipyards were being operated under contract by Kockums AB and Muskövarvet AB. In the autumn of 2019, as part of an upgrade of defence facilities and manpower, the naval base was revived, and it was announced that it would also serve as seat of the main headquarters of the Swedish Navy.
  One of the Swedish submarine incidents in October, 1982, took place just off Muskö naval base.
  A survey carried out in 2000 concluded that sedimentation in the tunnels leading to docks contained PCBs, organotin compounds and heavy metals, mainly mercury and copper.
  In 2019, Swedish naval command in the form of the Naval Staff returned to Muskö. In early 2020 it was confirmed that the base would be fully reactivated.
caption: The Muskö tunnel
exif: {"Image ImageDescription": "", "Image Make": "NIKON", "Image Model": "COOLPIX S51", "Image Orientation": "Horizontal (normal)", "Image XResolution": "300", "Image YResolution": "300", "Image ResolutionUnit": "Pixels/Inch", "Image Software": "COOLPIX S51V1.0", "Image DateTime": "2012:03:13 13:10:20", "Image YCbCrPositioning": "Co-sited", "Image ExifOffset": "284", "Thumbnail Compression": "JPEG (old-style)", "Thumbnail XResolution": "300", "Thumbnail YResolution": "300", "Thumbnail ResolutionUnit": "Pixels/Inch", "Thumbnail JPEGInterchangeFormat": "4084", "Thumbnail JPEGInterchangeFormatLength": "4899", "EXIF ExposureTime": "1/40", "EXIF FNumber": "33/10", "EXIF ExposureProgram": "Program Normal", "EXIF ISOSpeedRatings": "200", "EXIF ExifVersion": "0220", "EXIF DateTimeOriginal": "2012:03:13 13:10:20", "EXIF DateTimeDigitized": "2012:03:13 13:10:20", "EXIF ComponentsConfiguration": "YCbCr", "EXIF CompressedBitsPerPixel": "4", "EXIF ExposureBiasValue": "0", "EXIF MaxApertureValue": "17/5", "EXIF MeteringMode": "Pattern", "EXIF LightSource": "Unknown", "EXIF Flash": "Flash did not fire, compulsory flash mode", "EXIF FocalLength": "63/10", "EXIF FlashPixVersion": "0100", "EXIF ColorSpace": "sRGB", "EXIF ExifImageWidth": "3000", "EXIF ExifImageLength": "2120", "Interoperability InteroperabilityIndex": "R98", "Interoperability InteroperabilityVersion": "[48, 49, 48, 48]", "EXIF InteroperabilityOffset": "1054", "EXIF FileSource": "Digital Camera", "EXIF SceneType": "Directly Photographed", "EXIF CustomRendered": "Normal", "EXIF ExposureMode": "Auto Exposure", "EXIF WhiteBalance": "Auto", "EXIF DigitalZoomRatio": "1", "EXIF FocalLengthIn35mmFilm": "38", "EXIF SceneCaptureType": "Standard", "EXIF GainControl": "Low gain up", "EXIF Contrast": "Normal", "EXIF Saturation": "Normal", "EXIF Sharpness": "Normal", "EXIF SubjectDistanceRange": "0"}