This 10.5-mile trail near Lafayette in the East Bay is considered challenging but not technical. It should take us between 4 and 5 hours to complete. Expect a strenuous hike with great views. We’ll start early to avoid the hottest part of the day, but the trail is exposed so sun-protection is key. Note that there is also no potable water on the trail. Here’s how to calculate how much you’ll need.