An £8 million visitor centre which will be home to the Kent Mining Museum will not open until the spring of 2018, it has been revealed.

Problems building on a slag heap have slowed down work to transform the 121-hectare derelict colliery in Sandwich Road, Deal, which was due to open in the summer.

Construction of the visitor centre will now be finished before the end 2017 when the building will be handed over to the Betteshanger Sustainable Parks team by the Hadlow Group.

The group's deputy group principal and deputy chief executive Mark Lumsdon-Taylor said: "Building on a spoil heap was never going to be easy.

"While the building is now out of the ground and the steel frame is in place, the challenges presented by the groundworks have inevitably impacted on the timeframe.”

"We have an excellent track record in delivering on ambitious plans and the Betteshanger project is no exception.

"It will be delivered to the same outstanding standards that are synonymous with the group.

"We will continue to invest in the operations at Betteshanger this year, bringing forward some longer term developments and improved facilities."

Despite the setback, a full programme of events is planned including the arrival of The Beast, the world’s largest inflatable obstacle course, which will be making its UK debut at Betteshanger in May.

Extra facilities in the form of Tent Tipis, large-scale canvas tents with the capacity to seat 120, will be in place from the spring.

They will form the basis of a pop-up festival village, accompanied by a picnic area and street food stalls.