There are plenty of places to go for an urban hike. In the UK there is always a canal towpath, city walls, or old railway. You can also just explore the architecture of a city.
One source of hiking space in the bay area are the reclaimed landfills, as in your local Mt. Trashmore.
These parks often come with birdlife, sculptures, historical information boards, dog parks, cycling trails, cinder running paths, and you may even find geocaching still!
Today’s adventure was Seal Point park, San Mateo, with views of the final approach to SFO.