Red Top Mountain and Teanaway Ridge

Red Top Mountain, elevation 5,361 feet, is one of the better-known agate and thunderegg collecting spots in central Washington, sitting along Teanaway Ridge north of Cle Elum in Kittitas County [1][2]. The geology here is Swauk Formation sandstone cut by dikes of Teanaway Basalt, and rockhounds have been digging the "minefield" area — a stretch of ridge about a mile north of the Red Top Lookout — for decades; it's described as pockmarked with holes of all sizes from people working the ground for agate and thundereggs [2][3]. This is a real, well-documented, still-active site with actual driving directions, not a vague regional reference — a solid destination if you don't mind forest roads and some elevation.

From I-90, take exit 85 and head north on Highway 97 for 18 miles. Just past Mineral Springs Campground, turn left onto Forest Road 9738. After 2.6 miles, turn left onto Forest Road 9702 and drive 4.5 miles to the trailhead at a picnic area, elevation about 5,000 feet [3]. The Red Top Lookout sits at the end of the trail; the collecting "minefield" is about a mile north of the lookout [3].

This is dig-and-sort collecting in an established, heavily worked area — expect a shovel, screen, and rock hammer to be useful, and expect to be working alongside evidence of decades of prior digging (numerous holes across the ridge) [2][3]. Best worked in summer through early fall once the forest roads and higher elevations are snow-free; this seasonal note is general inference for this elevation, not sourced specifically to this site.

Red Top Mountain and the Teanaway Ridge area sit within National Forest land (Okanogan-Wenatchee National Forest) [1][2]. Confirm current U.S. Forest Service collecting rules for this specific district before digging, rather than relying on this page for legal limits. The access road involves unpaved forest roads (FR 9738, FR 9702) — a higher-clearance vehicle is worth having.