Skyline 50K
California's longest-running 50K, the Skyline 50K offers a welcoming challenge for all ultrarunners.
Race Date
Aug 2, 2026
Location
Castro Valley, CA
Quick facts
- Date
- Sunday, August 2, 2026
- Location
- Castro Valley, California
- Distance
- Half marathon (13.1 mi) + 50K
- Course
- Loop Course
- Terrain
- Road
- USATF certified
- Not listed
Highlights
Good For
Atmosphere
Course
The Experience
The Skyline 50K Endurance Run holds the distinction of being California's longest-running 50K, a testament to its enduring appeal. Held each August, this event has become a cherished tradition for many, welcoming both first-time ultrarunners and seasoned veterans to its course.
While specific course details regarding terrain and elevation are not provided, the race is known for its steady field trend, indicating a consistent and reliable experience year after year. The typical race-day weather offers a comfortable range, with temperatures averaging between 56–69°F, making for pleasant running conditions.
Race-provided description
Skyline 50k Endurance Run is the longest running 50K in California. This is a great event for first time ultrarunners and an old friend to veterans. Runs each August.
Course Info
Course Type
Loop Course
Terrain
road
Difficulty
Ultra-Flat
Net Drop/km
0 m (Flat)
Separation
0.0%
Also Offers
Quality Score
first year
no finisher counts yet
small race — neutral
needs a few years of results
3 timing sources
no finisher data yet
no winner time yet
typical high 69°F
Race Day Weather
5-year historical avgStart (Low)
56°
Afternoon (High)
69°
Pleasant conditions — light layers at start, comfortable by finish
0.0"
Precipitation
12 mph
Wind
81%
Humidity
Race Photos
Frequently asked
When is the Skyline 50K?
The Skyline 50K is held on Sunday, August 2, 2026.
Where does the Skyline 50K take place?
It takes place in Castro Valley, California.
What distances does the Skyline 50K offer?
The half marathon (13.1 miles), plus 50K.
Is the Skyline 50K course flat and good for a PR?
The Skyline 50K is a ultra-flat, loop course course.
HalfRuns editorial — independent, no paid placement.
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