Avid runners and some researchers say that the reason people do marathons over and over is because they forget how much it hurts. Then there are the people who remember exactly how much it hurts, but they keep going back for more.

With the 41st running of the Chicago Marathon coming up on Sunday, Oct. 7, we wanted to know what frequent Chicago Marathoners love (the energy, the tour of the city, the flat course) and loathe (the weather) about the race. But more important, we wanted to tap the hard-earned knowledge they’ve acquired after running the Chicago Marathon five or more times.

Here the top tips we got from these veteran racers:

Get There Early

Getting to the start of the Chicago marathon is relatively simple when you compare it to point-to-point races like New York or Boston. The race begins and ends in Grant Park, which is just east of the Loop and within walking distance of downtown hotels. But don’t let that trick you into thinking you need less time to get there.

“Be patient and give yourself plenty of time,” says Matthew Champa, 45, of Chicago. This year will be his seventh year running in the race. Despite living close enough to the start line that he can jog over, he puts together a plan for the morning. “It’s great, yes, but it’s still 45-plus thousand people.”

If you’re looking to drive or even want someone to drop you off, be prepared to walk a ways. “Really take a good look at the map and the layout of the corrals and the layout of the start, and get yourself in to the Loop early,” says Stephany Lane of Chicago.

Lane, 42, is running her seventh Chicago this year. “There are so many streets that are closed or only one way, so if you’re coming in a car, you never know how far away you’re going to have to get out.”

Champa recommends going to Grant Park the day before to get a sense of where your corral entrance is. Plus, if you’re from out of town, you can roll that into some sightseeing, as popular spots like Maggie Daley Park, the Art Institute, Buckingham Fountain, Millennium Park and the Museum Campus are all nearby.

Prepare For Any And All Weather

Everyone we talked to mentioned this. Chicago has notoriously unpredictable weather—for example, the 2007 race was cut short because of high heat and humidity, but two years later, the start-time temperature was in the low 30s.

“In 2006 I remember it snowed,” says Jim Gryzlak, 63, of Burr Ridge, Illinois, recalling a year of high winds and freezing rain. His seven races here have occurred in a variety of conditions. “I complained about it being so cold, and then 2007—I never complained about it being too cold again.”

The weather can change throughout the day, too. The early miles have the potential to be colder, not only because the sun hasn’t had much time to do its work, but also because that part of the course isn’t far off the lake. Depending on the day, the wind can play the role of a welcome breeze or an added chill. Heather Zeigler of Woodridge, Illinois is running her 10th Chicago this year and mentioned how it gets hot on the western out-and-back section (miles 14 to 17), and many people struggle.

“I think it’s kind of deserved its reputation for that part,” says Zeigler, 38. “But you always survive and get to come back to the city.”

The takeaway: Pack plenty of layers so you can accommodate whatever conditions Tom Skilling forecasts. And if your lodging is in the suburbs, be sure to check the weather for the city, not where you’re staying. “It can be different a few miles away,” says Champa. “There can be rain up north and not in the south—there’s like microclimates.”

Run Through Boystown With A Plan

Between miles 8 and 9, the course passes through Boystown, and it’s a party. “Boystown always hypes me up—it’s hard to go slow there,” says Lisa Keller, 45, of Chicago. This will be her eighth Chicago Marathon.

As energizing as this section is, it’s also very crowded, so if you want to keep pace, stick to the middle of the road. That’s what Lane does. She enjoys the fun atmosphere but knows to stay focused, because that early in the race, she’s still trying to settle in. “I do find that you’ll have a lot of runners and stop and enjoy the moment, which is great, but I’m usually trying to find that rhythm,” she says.

At the same time, don’t allow yourself to get frustrated and waste energy weaving through the congestion. “It gets crowded, especially in the first miles,” Champa says. “Don’t try to weave in and out. … That’s the time you need to conserve your energy.”

Get Fluid From The Later Tables At Aid Stations

Last year, more than 44,000 people crossed the finish line at Chicago. All those runners need hydration, which is why there are 20 aid stations along the course.

“The water and Gatorade tables are both very long—don’t try to grab fluids in the first table,” Champa says, adding that the earlier tables are very congested, and runners bump into each other there. “Jog through to the end tables. I don’t think people realize how long they are.”

Save Some For The Bridges

The course crosses the Chicago River six times—that means you have to run bridges. Don’t let the fact that Chicago is a flat course leave you unprepared for these energy-sucking sections. “The bridges should not be taken lightly,” Lane says. “The bridges have those open metal grates where the cars drive over and that’s a totally different feel on your feet. … You have to really watch your footing.”

And it’s not a river crossing, but one of the more challenging parts of the course is the section where Roosevelt Road passes over railroad tracks. “On Roosevelt, the little hill, it’s a small hill but it feels like a 90-degree hill like San Francisco,” says Carlos Ceballos, 45, of Willowbrook, Illinois. He would know: He’s done the second half of the San Francisco Marathon the last two years.

What’s Overhyped

Race veterans affectionately refer to the Roosevelt Road overpass as Mount Roosevelt, and each of the runners we talked to mentioned it as one of the harder parts of the race. There’s no denying that it’s difficult to tackle an incline when you’re 26 miles into a marathon.

But that’s just it: You’re almost done. It’s a mental game at that point. Ceballos, who is running Chicago for the seventh year in a row, says he reminds himself that it’s just 0.2 miles to the end as he pushes through the small hill. Champa pointed out that you can see the finish line from Roosevelt Road.

“That’s not a place where you can walk,” he says. “Pure adrenaline should be able to carry you over.” Also, it’s not even a tenth of a mile long.

Where It Gets Rough

Shade is hard to come by in the Chicago Marathon, especially during the second half. “That last half is all sun,” Gryzlak says. The hottest pockets often coincide with thinner crowds, too, like the western out-and-back (miles 14-17) and the stretch along 1-90, a.k.a. the Dan Ryan, about 22 miles in and after the excitement of Chinatown.

“That 24[-mile] area, you’re getting so close, but you’re just getting worn out,” Gryzlak says, adding that the crowds pick up again in mile 25. One piece of potentially good news: The course no longer runs along Archer Avenue in Bridgeport (before Chinatown), which several runners mentioned as a hot part of the course.

But there’s something to look forward to in those late miles. Lane pointed to the part around mile 24 near the Illinois Institute of Technology (IIT). “A lot of people say running through the section near IIT is terrible,” Lane says. “The crowd down there has gotten better, and there are lots of big trees, so that’s a last point of hope of shade before the finish.”

Where To Soak It All In

The Chicago Marathon course winds through 29 of the city’s 77 official neighborhoods—even for locals, it’s a great way to see the town. Here’s what runners had to say about their favorite parts:

Boystown (Lakeview East: Miles 8-9)

“It’s always so lively,” says Zeigler. “It’s early enough on that all the runners are all entertained and it really gets people going.”

Sedgwick Street (Lincoln Park: Miles 10-11)

“I like running down Sedgwick,” Keller says. “It’s really pretty, and there are lots of little kids trying to get high fives.”

Pilsen (Miles 19-20)

“The mariachi bands,” Ceballos says. “You can feel alive once again.”

Chinatown (Miles 21-22)

Other than Boystown, this was the area most often highlighted by the runners. As Lane says, “Chinatown never gets old.” It also provides a much-needed, late-mile energy boost. “The drummers in Chinatown—that is amazing,” Champa says. “You can hear them from like three blocks away.”