An offshore vessel said to have produced almost 150 million barrels of oil over 36 years has arrived in Shetland for decommissioning.
The Buchan Alpha's arrival in Lerwick had been delayed by poor weather.
The production vessel is being brought in to anchor for the removal of some of the deeper parts of the structure.
The Scottish government said the decommissioning was "a clear sign of the opportunities available in this emerging market".
The Buchan Apha will be brought alongside the newly-extended Dales Voe deepwater quay to be dismantled for recycling.
Work will begin on Monday and it is expected to take about 17 months to take Buchan Alpha apart.
The work will be done by the French company Veolia, and 35 jobs will be created by the project.
Originally a drilling rig, Buchan Alpha started production from the Buchan field in 1981.
It was taken out of service in May by operators Repsol Sinopec Resources UK.
Scottish government Minister for Business, Innovation and Energy, Paul Wheelhouse, said: "I am delighted that we have now seen the safe arrival of the Buchan Alpha in Lerwick.
"This is great news for Shetland and a clear sign of the opportunities available in this emerging market.
"The decommissioning of the Buchan Alpha provides Scotland and our supply chain with the opportunity to demonstrate our skills, capabilities and competitiveness in this area.
"We are committed to supporting Scottish industry win this decommissioning activity as an estimated £17.6bn is expected to be spent in the North Sea over the next decade as mature fields reach this stage in their project lifecycle.
"The Scottish supply chain is already capturing the majority of value from the decommissioning process, particularly in respect of well plugging and abandonment.
"But we are now actively supporting the industry, through the £5m Decommissioning Challenge Fund and the Decommissioning Action Plan, to identify further investment opportunities to capture contracts for later stages of the decommissioning process.
"The fund will specifically help to improve capacity at Scottish ports and increase the economic return to Scotland from a variety of removal, disposal and dismantling activities."
Sandra Laurenson, chief Executive of Lerwick Port Authority, added: "The arrival of Buchan Alpha is another significant milestone following more than a decade of decommissioning at Lerwick where Buchan is the largest project yet.
"Recent investment, extending the Dales Voe quay and laydown, and progressing plans for an ultra-deep-water quay as the UK solution to future requirements reflect our commitment to capability and competitiveness as a leader in the emerging decommissioning market."