The decisions to allow the building of a massive holiday development in Pembrokeshire have been backed by the Court of Appeal.
Bluestone would comprise lodges, a snow dome and a water park
The £60m Bluestone project sparked controversy as part of it will be built in Pembrokeshire Coast National Park.
The watchdog, the Council for National Parks (CNP), which challenged the High Court's decision to allow the scheme, said it was "deeply disappointed".
The developers argued that the 300 lodges would generate much-needed jobs.
A CNP spokeswoman had said the development would "desecrate" the countryside.
But the panel of three judges said they unanimously agreed that planning consent granted by the Pembrokeshire Coast National Park authority was legal.
They upheld the earlier High Court ruling in concluding that the authority's planning committee had correctly taken into account economic benefits in granting approval.
The appeal was seen as a test case in establishing the balance between local economic benefit and conservation issues.
Bluestone chief executive William McNamara said: "We are delighted with this unanimous decision which was not unexpected.
"Bluestone has now passed every legal, democratic and environmental test laid before it by two planning committees, 10 statutory advisors, an independent ombudsman, a High Court judge and finally three Lord Justices at the Supreme Court of Appeal.
'Setting a precedent'
"That is seven professional judgements that all bear witness to the propriety of the Bluestone decision and this clears the way for work to begin on this major new holiday village development in the UK."
Mr McNamara added that he would be asking questions about the £100,000 legal costs he said the park authority will face, which will be covered by tax-payers.
Pembrokeshire National Park Authority supported the development, saying it would not cause environmental damage.
But the CNP, the watchdog which monitors development in national parks across Wales and England, had worried about setting a precedent for developments in other parks.
It said the appeal court had "missed an opportunity" to clarify the legal rules for deciding major planning applications in the parks.
Ruth Chambers, CNP¿s Head of Policy, said: ¿Allowing the Bluestone holiday village to go ahead has muddied the waters for the public and developers alike".
The CNP called the judgement "deeply disappointing" and said it was considering the possibility of a final appeal to the House of Lords.
The case went to Court of Appeal in June after the CNP was refused permission to appeal against a High Court ruling it lost in December 2004.