Golden Gate Half
A 5K is about 3.1 miles, and a 10K is about 6.2 miles. That's a lot of running, but long-distance races don't stop there. There's half marathons (13.1 miles), marathons (26.2 miles), 50K's (31 miles) and 100K's (62 miles). Anything beyond that is crazy. I was in San Francisco today with the simple intention of running across the Golden Gate bridge to Marin and back. What I did was much more than I expected.