An opencast mining scheme which Wakefield Council warned would threaten the future of the Yorkshire Sculpture Park and Bretton Hall estate has been refused by a planning committee.
The Kirklees Council committee ruled that plans to extract coal and fireclay on land off Litherop Lane, Clayton West, would harm green belt land and historical sites.
Wakefield Council had feared the scheme would spoil their plans to invest in the area, which include a new luxury hotel at Bretton Hall and the creation of hundreds of jobs.
English Heritage also objected to the proposals.
The 120-bed hotel at Bretton was granted planning permission in February, and developers Rushbond plc hope to have it built by 2015.