ICGV Þór (Thor) is an UT 512L type offshore patrol vessel designed by Rolls-Royce for the Icelandic Coast Guard, built to replace the aging ICGV Óðinn. The construction of the ship was approved by the Icelandic government on 4 March 2005. Construction of the ship began at the ASMAR Naval Shipyard in Talcahuano, Chile, on 16 October 2007. Construction was delayed by over a year due to the 2010 Chilean earthquake, but damage to the structure of the ship was not as detrimental as had been expected. After repairs, the ICGV Þór was delivered to ICG personnel on 23 September 2011 in Chile. She arrived in Reykjavík on 27 October 2011. Its main tasks are EEZ patrol, fishery inspection and search and rescue support. The ship is named after the Norse god Thor.

The Icelandic Coast Guard is the Icelandic defence service responsible for search and rescue, maritime safety and security surveillance, national defense, and law enforcement. The Coast Guard maintains the Iceland Air Defence System which conducts ground-based surveillance of Iceland's air space and operate Keflavik airbase. It is also responsible for hydrographic surveying and nautical charting.