Crissy Field Walk
Difficulty Level: Dead flat
In my opinion, this is the possibly the world's best urban walk, running between the Marina and Fort Point beneath the Golden Gate Bridge. Going west, you get bridge views all the way. Coming back, you'll see the San Francisco city skyline. The path is dead flat and smooth and perfect for walking or running, used by locals and tourists alike.
Park at Fort Point to make the round trip and follow the edge of the water until you reach the walking path. You can also start at Marina Green. Follow Marina Blvd west toward the Golden Gate Bridge, going straight as the road changes its name to Mason, to the parking area a short distance down.
Telegraph Hill Hike
Difficulty Level: Somewhat steep with lots of stairs, but can be done downhill all the way
For some of San Francisco's most surprising scenery, take a Telegraph Hill walk. Telegraph Hill is easily recognized from almost anywhere in the city by Coit Tower, which is located at the top. This walk is far from flat, but it's easy to do it all downhill, as described below. Reverse the directions for a "high intensity" workout.
- Start in North Beach on Stockton Street. Look around and find Coit Tower.
- Walk up any street you like toward the tower. I like to use Lombard Street. You can also avoid the climb by taking the #39 city bus from Washington Square.
- Visit Coit Tower and take advantage of the restrooms while you're there. Pick up water from the ever-present street vendors if you need it.
- Where the street enters the parking area, find the steps going down. Follow them.
- It's hard to get lost from here. Just take the steps down the hill. No matter which small turn you take, you'll eventually end up at the bottom of the hill. You'll walk through an area of houses and well-manicured gardens, where sidewalks and steps replace streets. If you're a film fan, you may recognize the apartment house at 1360 Montgomery, where Lauren Bacall gave refuge to Humphrey Bogart in the movie Dark Passage.
- When you reach sea level again, you will be on Battery Street. Turn left to get to the waterfront.
Walk the Golden Gate Bridge
Difficulty level: Flat
You can look at the Golden Gate Bridge all day long, but until you take a walk on it, you won't truly know what it's like. At mid-span, you stand 220 feet above the water's surface, and passing ships below look like small toys. The distance from one vista point to another is 1.7 miles, but even a short hike (or to the middle and back) will give you a feel for the structure. It can be windier on the bridge than inland, so take an extra layer and be sure everything is secure so you don't accidentally drop it into the Bay.
Parking at the bridge's south vista point is limited and expensive, which may tempt you to rush instead of exploring. Instead of parking there, drive away from the lot (with the bridge behind you) and turn left out of the parking lot onto Lincoln. You will find a gravel lot not far down on your left. If you are approaching from the Presidio on Lincoln, the lot is just across from the two-story houses that were once the Presidio officer's quarters. You'll have to pay to park there, but you can stay much longer than at the vista point.
Hyde Street Climb
Difficulty: Steep climb
Hyde Street is another interesting urban hike with a steep climb. Hyde is an especially good hike for photographers. Start near Ghirardelli Square at the Hyde Street cable car turnaround. Follow the cable car line up the hill on Hyde Street. Stop at Lombard Street to watch the craziness on the crookedest street. Return the way you came, or walk down Lombard all the way to North Beach, where you could pick up the Telegraph Hill walk if you still have energy.
Angel Island Walk
Difficulty: Varies, with some trails fairly flat
Angel Island is across the Bay from the city of San Francisco. A climb to the top of the island rewards you with 360-degree views of the city and the bay. You can get there from San Francisco by ferry, or drive across the Golden Gate Bridge to Tiburon and catch a ferry to Angel Island from there. The ferries run much more frequently from Tiburon than from San Francisco. Angel Island Company offers a number of activities including bicycle and kayak rentals.
Guided Hikes and Walks
If you'd like to do some hiking/vigorous walking but don't want to go by yourself, try Urban Hikers, who host several guided hikes, including ones that cover some of the same areas mentioned above.
The San Francisco Walking Tours guide has more options for walking around San Francisco.