The Madrona Rim is a ficticious resort situated within the San Juan Islands of Washington State.
The tree shown (on the right) is located on a bluff overlooking the ocean inlet of Orcas Island, WA, where many "madrona" trees grow. The Pacific Madrone (inset below) has a unique bark and appearance; it is an especially beautiful tree when direct sun illuminates it's leaves and branches.
The madrona tree is commonly found in the Pacific Northwest on coastal ridges on relatively sunny exposures that overlook the sea. In the book, Delivering Diamonds, madrona and evergreen stands are where Claire seeks refuge, especially after the tragedy at her resort.
Here are links to learn more about the Pacific Madrone and other trees indigenous to western Washington:
Parallels are made in Delivering Diamonds comparing human characteristics to the amazing trees commonly found in the Puget Sound region of Wasington State.