Iluvatar, is located in Prairie Creek Redwoods State Park of Northern California, among a group of trees called Atlas Grove. The location is unpublished. 'Atlas grove' including Iluvatar, is one of the most carefully studied areas of forest in the world. Just measuring of Iluvatar required 5 skilled climbers for over 20 days.
The Atlas Grove (with Iluvatar) is said by author Richard Preston, to have been discovered by an amateur naturalist Michael Taylor, about March 1991. This claim contrasts with information from Oregon Arborist, M. D. Vaden, who found old symbols in the grove, indicating a predating history of the grove.
Iluvatar is supposed to have up to 220 reiterated trunks; one of the most complex tree structures known.
This coastal redwood is surrounded in the grove by other old coastal redwoods including Atlas Tree, Gaia, Pleiades, Ballantine, Promethius, Bell, Zeus and others. Ballantine was named after a real man. Some were named after ancient Greek gods. Neighboring species include Pseudotsuga menziesii, Picea sitchensis, Acer macrophyllum, Rhamnus purshiana, Umbellularia californica, Tsuga heterophylla, Chamaecyparis lawsoniana and Lithocarpus densiflorus.