Staff and volunteers at the Forestry Commission's National Arboretum at Westonbirt are celebrating after the arboretum was awarded a grant of £1.9 million from the Heritage Lottery Fund (HLF).
The grant means phase one of the Westonbirt Project - a development plan which includes restoration of the Grade I registered landscape and the construction of a new Welcome Building and car park - can begin in 2013.
Simon Toomer, Arboretum director, said: "This is a great step forward in realising our ambitious plans to raise the level of the arboretum's visitor and learning facilities to match that of its world class tree collection.
"This award will go a long way to help make Westonbirt a place where all visitors can enjoy and learn so much more about the arboretum and its trees."
Richard Bellamy, head of HLF South West, said: "Westonbirt has been looking spectacular thanks to the autumn colours which attracted huge numbers of visitors this year.
"We were really impressed with the Forestry Commission's vision regarding conserving key parts of this wonderful landscape and also making much-needed improvements to visitor facilities.
"Plans for a volunteer programme - Westonbirt's very own 'Gamesmakers' - will also make a huge difference to both conservation and education work on site."
And Chris Packham, environmentalist and TV presenter, said: "This announcement is particularly heart-warming set amongst the awful backdrop of news of our endangered trees.
"I can't stress enough the importance of this particular arboretum - it's the natural world's equivalent of an outdoor museum and gives us a much greater understanding of the variety and value of trees.
"The Heritage Lottery Fund has a fantastic track record for supporting the UK's landscapes and wildlife and this investment of nearly £2m will delight the many of us who are passionate about trees and the environment."
Construction of the new car park will begin in the New Year. The car park will be followed by construction of the Welcome Building during the summer.
Inside the Welcome Building, visitors will find up-to-date information about what is happening around the arboretum - from family activities and free guided walks to information about the tree collection.
Once the Welcome Building is completed, the site of the current car park, which is located on Grade I registered land, will be restored to wildflower-rich grassland.
The HLF funding will also allow the arboretum to engage with wider communities through new projects and more resources. Projects with community groups at risk from social exclusion are planned as part of this work.
The awarding of HLF funding will also allow the arboretum to look ahead to later phases of the Westonbirt Project, which include a tree walkway and a tree management centre.