ESTES PARK — Rocky Mountain Conservancy is working to raise $3.6 million to buy 40 acres that are privately owned but within the boundaries of Rocky Mountain National Park.

The nonprofit partner for the national park has already raised $1.5 million and, on Wednesday, announced the donation campaign to the public.

Honoring a handshake deal from their grandfather, the current owners of Cascade Cottages offered the property first to the national park. The Trust for Public Land negotiated an agreement for the nonprofit to buy the land, which later will be transferred to the national park.

The 40 acres is just inside the Fall River entrance to the park and is split by Fall River Road. Half is undeveloped and prime habitat for bighorn sheep, while the other half houses about 12 primitive cabins that have been available as vacation rentals.

For more information on the project or on donating, visit www.RMConservancy.org or call 586-0108.