The SF Marathon course

Dark start on the Embarcadero at Market, water on your left and the whole city still asleep. It is flat and it is crowded, so run it slower than the adrenaline wants.

Jefferson Street takes you through Fisherman's Wharf while it is still shuttered. The mile reads flat on the whole, but the road starts tipping up in the last stretch of it.

A short climb on McDowell and Van Ness tops out early, then Marina Boulevard hands every foot of it back. Net for the mile is nothing, which is a fair description of how these first three should feel.

Marina Boulevard runs level into Mason Street and the edge of Crissy Field. The long pull toward the bridge begins somewhere in here, so shorten your stride before you have to.

Mason Street, flat, dark, the bay off to your right. Nothing to do but hold the effort and let the field sort itself out.

Marine Drive hugs the water, then Long Avenue starts turning the screw. The climbing is real from here, and the next mile is worse.

Battery East Road and Lincoln Boulevard deliver the biggest single mile of climbing on the course, then the Golden Gate opens in front of you. Forget pace entirely and just get to the tower.

Out on the deck now, with wind off the ocean and fog that may or may not let you see the far tower. The road gives a little back, so take it and stop fighting the crosswind.

Off the north end and onto Alexander Avenue, dropping toward the Marin side. Free speed, though it is the kind that bills your quads later.

Alexander bottoms out onto East Road for the biggest drop of the race so far. Let it run, stay tall, and keep off the brakes.

East Road turns into Moore and Center and the ground turns against you. Everything you just descended gets charged back over the next mile and a bit, at the steepest sustained grade of the day.

Redwood Highway hauls you back up to bridge level. Grind it out and remember the top is a checkpoint, not a reward.

Back on the Golden Gate, southbound, the city ahead of you instead of behind. The deck runs downhill, so let your legs turn over and stop doing math.

One short sharp kick off the bridge onto Merchant Road, then Lincoln Boulevard tilts down into the Presidio. Halfway lands in this mile, and the hardest climbing on the course is already behind you.

Lincoln becomes El Camino del Mar and then 27th Avenue, drifting gently downhill. Use the next few minutes well, because a long steady climb starts inside this mile and does not quit until past 17.

27th meets Fulton and Crossover Drive carries you into Golden Gate Park. The road is climbing again, quieter now, and the trees make it feel slower than it is.

Crossover to Transverse to Blue Heron Lake Drive, the high ground of the park. This is the last real climb of the day, so spend what it costs and get it behind you.

Around the lake and out onto Martin Luther King Junior Drive, finally pointed downhill. Shade, quiet pavement, and the first mile in a long while where you can breathe and think about the finish.

Still inside Golden Gate Park, flat and green, with 20 close enough to smell. Whatever pace you can hold here is the pace you will be defending the rest of the way.

Out of the park and onto Haight Street with the road falling away. Twenty is where this course starts giving instead of taking, but only if your quads survived the bridge.

Haight keeps dropping through the Lower Haight to Buchanan and Hermann. Genuine downhill and genuine speed: check that your form has not collapsed into a shuffle.

Hermann feeds Guerrero and 16th Street for the steepest drop of the entire race, straight into the Mission. Do not cash the whole check here, because the road goes flat for the rest of the day.

16th to 17th to Wisconsin Street, up onto the Potrero flats. The falling stops here and the course asks you to actually run again.

Dogpatch now: 19th Street, then Illinois and Indiana. Level ground, open and industrial, and the finish is a straight line away.

Terry A. Francois Boulevard along the Mission Bay waterfront, then Third Street toward the ballpark. Flat and exposed, and the last mile where a decision about pace still changes anything.

King Street and a final turn onto the Embarcadero, the same water you started beside in the dark. Flat to the line, and the city has been awake for hours.