AMBLEWAY Wildest hikes

Mount Diablo State Park

Fossil Hill–Willow Spring Pond, 10 sights

15.9 mi · ▲ 2,606 ft · 6 hr 36 min

Fossil Hill–Willow Spring Pond, 10 sights is a 15.9-mile out-and-back in Mount Diablo State Park near Rock City, CA. The route passes TwinPonds, Twin Ponds, Willow Spring Pond and Bramhall Pond before reaching Fossil Hill at the turnaround, 8 miles in. It climbs 2,606 ft, with sections as steep as 17% grade, and is mostly dirt. It scores 72/100 on the Ambleway Wildness scale: backcountry feel.

Elevation

0 mi217 – 1,752 ft · steepest grade: 17%16.6 mi

Getting there

Trailhead: Trail Through Time 37.85019, -121.93391
Nearest town Rock City, CA
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Directions

AMBLEWAYwww.ambleway.com

Fossil Hill–Willow Spring Pond, 10 sights

15.9 mi · ▲ 2,606 ft · 6 hr 36 min

Elevation 218–1,752 ft

Out & Back · Mount Diablo State Park

Trailhead: Trail Through Time · 37.85019, -121.93391

Weather Sep 20: sunrise 6:55 AM · sunset 7:09 PM

Toilets at the trailhead · Drinking water at the trailhead · Parking lot at the trailhead

  1. Start on Trail Through Time, heading NW.
  2. 0.2 miBear left onto Wall Point Road, heading NW.
  3. 1.1 miTurn left onto Secret Trail, heading NW.
  4. 50 ftTurn right onto Wall Point Road, heading NW.
  5. 2.2 miContinue straight onto Briones to Mt. Diablo Regional Trail, heading NW.
  6. 0.3 miBear left, heading N.
  7. 1.3 miBear left, heading NW.
  8. 0.1 miBear right, heading NW.
  9. 150 ftContinue straight onto Borges Ranch Trail, heading NW.
  10. 450 ftBear left, heading NW.
  11. 0.2 miPass TwinPonds.
  12. 50 ftPass Twin Ponds.
  13. 350 ftTurn left onto Twin Ponds Loop Trail, heading NW.
  14. 50 ftContinue straight onto Borges Ranch Trail, heading NW.
  15. 0.2 miSharp left onto Briones to Mt. Diablo Regional Trail, heading NW.
  16. 0.9 miPass Willow Spring Pond.
  17. 0.2 miBear left, heading W.
  18. 0.6 miPass Bramhall Pond.
  19. 250 ftTurn left onto Fossil Hill Trail, heading NW.
  20. 250 ftTurn right onto Indian Creek Trail, heading W.
  21. 0.3 miContinue straight onto Fossil Hill Trail, heading S.
  22. 0.1 miTurn left onto Kovar Trail, heading NW.
  23. 250 ftReach Fossil Hill, then turn around and head back the way you came.
  24. 250 ftTurn right onto Fossil Hill Trail, heading NW.
  25. 0.1 miContinue straight onto Indian Creek Trail, heading S.
  26. 0.3 miTurn left onto Fossil Hill Trail, heading N.
  27. 250 ftTurn right onto Briones to Mt. Diablo Regional Trail, heading SE.
  28. 0.6 miTurn right, heading NE.
  29. 1.1 miSharp right onto Borges Ranch Trail, heading E.
  30. 0.2 miContinue straight onto Twin Ponds Loop Trail, heading SE.
  31. 50 ftTurn right onto Borges Ranch Trail, heading SE.
  32. 0.5 miBear right onto Briones to Mt. Diablo Regional Trail, heading SE.
  33. 1.6 miContinue straight onto Wall Point Road, heading E.
  34. 2.2 miTurn left onto Secret Trail, heading S.
  35. 50 ftTurn right onto Wall Point Road, heading S.
  36. 1.1 miBear right onto Trail Through Time, heading S.
  37. 500 ftArrive back at the trailhead.

Each distance is the walk from the previous step. Tap a step for a map of its junction.

Trail map, photos and weather for this hike: www.ambleway.com/hikes/willow-spring-pond-willow-spring-pond-out-back-6-lakes-21-km-1e3d

Trail surface

96% dirt4% unspecified

Weather

Sunrise 6:55 AMSunset 7:09 PM

Sunset

The best sunset spot on this hike is 0.1 mi in (~4 min). Leave by 6:45 PM for the 7:09 PM sunset. Back at your car by 7:28 PM — 8 min before dark. Car visible from the viewpoint

More sunset hikes nearby

Good to know

  • Toilets at the trailhead
  • Drinking water at the trailhead
  • Parking lot at the trailhead

Other ways to reach this destination

More from Trail Through Time Trailhead

Hikes near Rock City, California