Advice: I brought a 32 oz water bottle with me (filled with water), and used all of it a couple miles before the end. Wasn't a crisis or anything, but I could definitely have used some more water.

For those unfamiliar with the trail: crosstowntrail.org/

Also, if you have a "national parks passport", bring it! You can get it stamped at the end, which is Land's End, part of the Golden Gate National Recreational Area.