Bay Farm Island Loop Trail is a 6 mile moderately trafficked loop trail located near Alameda, California that features beautiful wild flowers and is good for all skill levels. The trail offers a number of activity options and is accessible year-round.
The brochure is here: http://alamedaca.gov/sites/default/files/document-files/gs_brochure.pdf
Nice views of SF bay. Flat but a little bumpy in the bike in some sections
A nice flat walk with great views -- at least for the first half or so. If you do the whole loop counterclockwise the second half (ish) is a lot more industrial and less scenic.