The New York City Marathon is not where world records are set.

Those blazing times are clocked on flat and fast courses in Chicago, Berlin and London. Runners there can easily be dropped off by a cab shortly before the starting gun, yawn and get going.

This is New York.

This is a marathon for 50,000 people who go on a public transportation odyssey to reach a brutally challenging course that crosses five bridges and five boroughs.

It’s a race for runners who want to prove this city deserves to be called the greatest on the planet, home of the greatest marathon in the world.

Marathon Sunday might as well be a holiday. It’s a reason to cheer on a random person doing a random thing on a random day for God knows what reason, but hey — go you. Write your name on your T-shirt, and you’ll feel like a celebrity for 26.2 miles.

Here’s a guide to the New York City Marathon, from the vantage point of its 50,000 lucky runners.

To run the New York City Marathon, you’ve got to get to the start line.

If you aren’t taking a chartered bus over the Verrazzano-Narrows Bridge before it closes to traffic, you will probably take some combination of a cab, a subway, a ferry and a bus. You will soon know enough about public transit to run the Metropolitan Transportation Authority, the state agency that oversees the subway and buses.

If you get confused by the maps and the logistics, follow the people wearing layers of fuzzy clothing and carrying bananas and water bottles in clear plastic bags. They’ll lead you to the starting village.

On the map for the marathon, you’ll see a big dot denoting the start line. What you won’t see is the sprawling village there — a holding area for the tens of thousands of people nervously waiting to be called up for their turn.

There are tents with therapy dogs and tents with coffee. There are tents with groups stretching and tents with bagels. There are 1,700 toilets and an unbelievable number of people in line for their pre-race poop. You can laugh, but it will be you soon enough.

Finally, your wave of runners is called to the start line. Suddenly, you are at the base of the Verrazzano-Narrows Bridge and military and police officers are restraining your energy with strings (really). With the sound of a cannon, the officers let you go free, and Frank Sinatra welcomes you to the streets of New York.

But remember that you are at the base of a two-mile bridge. That means your legs will be forced to slow just a bit, and that’s a good thing. Look to your left. See Manhattan? One World Trade Center? The Empire State Building?

Don’t get too excited too quickly — you have a lot of miles ahead of you.

There’s usually someone holding a sign at the other end of the bridge welcoming you to Brooklyn. They are the first of the millions of spectators who will greet you in their neighborhoods.

Turn right onto Fourth Avenue and lock in. Four and a half miles straight through Bay Ridge, Sunset Park and Park Slope will slingshot you to Downtown Brooklyn.

The crowds on Fourth Avenue build as you get closer to Barclays Center, and it’s easy to get carried away. Salute the bands, give high-fives to children and thank the volunteers handing out water. You already have eight miles under you.

Some of the best parties on the course happen on the stoops of brownstones along Lafayette Avenue. There will be music. There will be dancing. Take that energy in and give it right back. Dance a bit, smile and thank everyone for cheering you on.

Now hold that crowd support close. You’ll need it later.

The crowds quiet down in South Williamsburg, a perfect time to take stock. You’ve now reached double digits in your mileage. Do you need more water? Running gels? Are you going too fast? Too slow?

Take some deep breaths. Soon you’ll be in the party pockets of North Williamsburg and Greenpoint, where there’s a good chance you’ll be offered bananas, doughnuts and shots of alcohol.

Partake at your own risk — you have to run over the Pulaski Bridge into Queens soon.

It’s natural to turn into Queens and take an exaggerated gulp. Yes, that’s the Queensboro Bridge ahead, and yes, it’s big and long.

That’s why the crowds in Long Island City are so good. Get some extra high-fives here as you zigzag through the borough for a quick two miles. Then a quiet will descend as you charge up the bridge. The only thing you will hear is the pitter-patter of running shoes and the labored breathing of marathoners.

After a while, some runners will start to cheer, knowing that even with 15 miles done, you all need some encouragement. Let out a “woo” that will echo as you push each other along, and share some uplifting words. Listen to your breathing and keep calm.

As you exit the Queensboro Bridge into Manhattan, you’ll lean to your left and run straight into a wall of sound. On either side of First Avenue, crowds four to five people deep will be craning their necks looking for their loved ones.

You have 10 miles to go. Use the hills on First Avenue, and keep your eye on the street numbers. The Willis Avenue Bridge to the Bronx is waiting for you past 125th Street.

No borough shows more pride than the Bronx. The local run crews bring the music and spirit you’re going to need when you hit mile 20.

Break through that wall — as a sign will inevitably say — and then get over that last bridge. The energy of the Bronx will drive you back into Manhattan.

You’ll turn back into Manhattan on Fifth Avenue and realize that this is the street that will take you to Central Park, home of the finish line. You’ve got less than 10 kilometers (about 6.2 miles) to go. This is where the race really starts.

Keep your cool as you run from 138th Street to Central Park North at 110th Street. That’s where a hill will begin. It’s not a mountain, but beginning near mile 23, it might as well be. Put your head down and your knees up, pumping those arms.

A sharp right on 90th Street will take you into Central Park, and suddenly it will dawn on you.

You have just over two miles left.

You are in the park, the park you have been running toward for the last 24 miles. You are really going to do it. You are really going to finish this thing.

There are some hills in the park — don’t say we didn’t warn you — but take them as they come.

Keep it together. Say that to yourself a few times now.

You will be spit out of the park (on a downhill) to run along Central Park South. When you turn right back into the park at Columbus Circle, there will be hundreds of flags waving to welcome you home. For the first time, people screaming “you’re almost there” are telling the truth.

Your whole body should be screaming, too. That means you’ve done this thing right. Let your adrenaline pull you over that final incline.

Cross the finish line in one last stride and finally, finally, stop running. Put your hands above your head and breathe.

Shuffle along toward the medals and smile.

You earned it.