There are plenty of perks to running a small-town marathon, such as simpler logistics and less crowded streets. However, running one of the biggest marathons in the US or elsewhere, with a humongous field size, offers unique benefits, such as prestige, spectator support, and expert organization.
For example, events like the Chicago Marathon and New York City Marathon, which are part of the Abbott World Marathon Majors, are recognized globally and meticulously organized, ensuring smooth logistics, safety, and ample support throughout the course.
Hearing the thousands of enthusiastic spectators cheering you on as you run down the main drags and pass by famous landmarks is exciting and motivating. These major marathons foster a strong sense of community among runners of all skill levels, creating a welcoming environment that celebrates shared goals and personal achievements.
With running expos, post-race celebrations, and the opportunity to connect with fellow runners, these marathons provide a rewarding experience that makes them some of the most sought-after events in the running world.
Have I convinced you to consider running one of the biggest marathons in the US yet?
The 10 Biggest Marathons In The US
Although the field size and number of finishers in marathons vary yearly, we have created a list of some of the biggest marathons in the US for you to choose from.
#1: TCS New York City Marathon
The New York City Marathon is one of the Abbott World Marathon Majors held annually in November.
It had a whopping 51,543 finishers in 2023, making it one of the world’s largest marathons.
The iconic NYC Marathon course winds through all five boroughs, including Staten Island, Brooklyn, Queens, Manhattan, and the Bronx, circling back to Manhattan’s famous Central Park for the finish line.
The course is rolling and traverses city streets and bridges, lined nearly the entire way by what is said to be millions of enthusiastic spectators.
It’s a fantastic way to get a true slice of New York City’s energy, culture, and history.
#2: Bank of America Chicago Marathon
The Chicago Marathon had 52,150 finishers in 2024.
It is another one of the six Abbott World Marathon Majors, and in terms of the three World Marathon Majors in the USA (alongside the Boston Marathon and the New York City Marathon), the Chicago Marathon has the fastest course.
Because of its flat course, the Chicago Marathon is extremely popular among runners looking to set a personal record (PR) or hit a qualifying time for the Boston Marathon.
There is always a strong elite field, including championship and Olympic runners, making it an exciting marathon to watch. As of 2024, both the men’s and women’s world records were set in Chicago.
#3: Boston Marathon
Not only is the Boston Marathon one of the largest marathons in the US, but it is also one of the most popular and famous marathons around the world. In 2024, there were 25,554 finishers.
The Boston Marathon is the oldest continually running marathon in the world, having been held every year since 1897.
The point-to-point Boston marathon course starts in Hopkinton, Massachusetts, and finishes on Boylston Street in Copley Square.
Runners must qualify for the Boston Marathon, or they can participate by fundraising for a charity. However, the allure and prestige of needing to qualify make the Boston Marathon a bucket list marathon for many runners.
The Boston Marathon course is surprisingly difficult for such a major city marathon. It starts on a downhill for almost the first 10K of the race, which is deceptively tricky.
This can come back to bite you later in the race, as there is a series of significant hills around the 15-mile mark, including the infamous Heartbreak Hill.
#4: Marine Corps Marathon
The Marine Corps Marathon is one of the most popular marathons in the United States and one of the largest in field size, hosting around 20,000 participants annually.
Held in the nation’s capital, Washington, DC, the Marine Corps Marathon always sells out in record time. This fan-favorite marathon has been dubbed “The People’s Marathon” and is popular with first-time runners looking to finish the marathon as well as experienced runners.
It is also particularly popular among veterans of the armed services and other first responders and heroes.
The course is relatively flat and fast, taking runners past some of the capital’s iconic landmarks.
Some of those landmarks include Arlington National Cemetery, Georgetown University, the Kennedy Center, the Lincoln Memorial, the FDR Memorial, the Jefferson Memorial, the Martin Luther King, Jr. Memorial, the Korean War Memorial, the WW2 Memorial, the DC War Memorial, the Washington Monument, the Smithsonian Museums, and the Pentagon.
The course also spends a lot of time along the serene Potomac River.
Plus, the marathon has a generous 7-hour time limit, allowing even slower runners to enter and finish.
#5: San Francisco Marathon
In 2024, over 31,000 participants ran the San Francisco Marathon.
Running the San Francisco Marathon is an exhilarating experience filled with stunning sights and vibrant energy.
As you race, you’ll be treated to breathtaking views of the San Francisco Bay from the iconic Golden Gate Bridge while passing through famous parks and neighborhoods like Fisherman’s Wharf, Marina Green, and the Mission District.
The course isn’t the fastest on the list, as its hills offer a challenge, but the views are well worth it.
#6: Chevron Houston Marathon
You could also start your year with the Chevron Houston Marathon, held annually in mid-January and with a field of around 30,000 runners.
This marathon is known for its flat, fast course, making it a favorite for runners looking to PR or qualify for Boston.
The event is full of community spirit, as more than 200,000 spectators cheer on participants, providing a lively atmosphere and featuring a mixture of urban and park settings along the route.
#7: Los Angeles Marathon
The Los Angeles Marathon is a massive marathon held in the second-largest city in California. In 2024, just under 28,000 runners finished the race.
Because the race course is very close to Hollywood, there are often exciting celebrity sightings, which can be fun if you are into pop culture, movie stars, and trying to spot A-list celebrities among a massive field of marathon runners.
Many runners also aspire to run the Los Angeles Marathon because it is a great destination race. The city has incredible restaurants and entertainment options, various national parks, and other intriguing tourist destinations within driving distance of the city.
#8: Philadelphia Marathon
Nearly 11,500 participants ran the Philadelphia Marathon in 2023. This late November race is relatively flat and fast and often draws runners who don’t enter the New York City Marathon.
This marathon showcases the city’s rich history and vibrant culture. Its scenic course winds through iconic landmarks such as the Philadelphia Museum of Art and Fairmount Park, offering stunning views of the skyline and the Schuylkill River.
It starts near the Philadelphia Art Museum, where Rocky’s famous steps are seen. Before the race begins, you are guaranteed to hear “Eye of the Tiger” blaring through the loudspeakers.
Runners enjoy a festive atmosphere with enthusiastic crowd support and live entertainment along the route.
#9: Miami Marathon
The Miami Marathon in Florida has a field size of around 18,000 runners.
The flat and fast road race course is set against a stunning backdrop of palm trees and picturesque coastal views winding through iconic neighborhoods such as South Beach, Coconut Grove, and Little Havana.
Runners will enjoy a lively atmosphere with music, cheering crowds, and entertainment along the route, creating a festive race day experience.
#10: Medtronic Twin Cities Marathon
Even though this marathon has a field size of just under 10,000, we decided to include it on our list because, despite its decent field size, it still has a bit of a “small city” feel.
This was actually our Managing Editor Katelyn’s first marathon, and she said she loved it because of its scenic course, which showcases the beauty of Minneapolis and St. Paul.
The course takes you through vibrant neighborhoods and parks and along the stunning shores of the Mississippi and Minnesota Rivers.
With its community spirit and pretty landscapes, the Twin Cities Marathon is often dubbed the “Most Beautiful Urban Marathon in America.”
Believe me, there are plenty of other exciting options in addition to this list, such as the Honolulu Marathon, The Big Sur, The Rock ‘n’ Roll circuit, and the Walt Disney World Marathon race weekend, not to mention some of the biggest marathons around the world, like Berlin and London.
Have you chosen your favorite?
What about running one of the most beautiful marathons in the world?
If you are into scenic routes, check out our guide to some of the most beautiful marathons to put on your bucket list:
they may be the biggest, but that doesn’t mean they are the best. I think one of the best marathons– view, course, support– is the St. George Marathon.