For a couple of years, this was my local parkrun and it's honestly such a joy. The location is second to none - on a stretch of flat, reclaimed land near the Golden Gate Bridge. The views are the best in the city - the sparkling blue bay, the green of the headlands across the water and that gorgeous orange bridge on the horizon. It meets at the cafe near the SF Yacht Club. It's generally a small group - maybe 30 or 40 people. Half are locals, half are tourists, but it's really friendly. You can park in the car park for free of Old Mason Street. There are loos next to the yacht club harbour. The course is dead flat. You'll run west towards the bridge, do a triangular loop at the end and then run back. The surface is hard-packed sand trail - it's generally fine to run on but after rain, there are some significant puddles. Crissy Field is also generally busy with people - lots of families with kids on bikes and LOTS of people with dogs, so run with your eyes open and be respectful to other park users. At the end, people are chatty and friendly and you get to have your photo taken with the bridge in the background, and then most people head over to the coffee and donut stand by the yacht club. The coffee is excellent, the donuts are also excellent. It's pretty lovely. I got my 5k PR here on this flat, fast course and it was one of the best days ever If you're in the City by the Bay, definitely do this.