My marathons

21K Buenos Aires

The organiser has not published a date. Buenos Aires
Buenos Aires
Buenos Aires. Photograph by ProtoplasmaKid, CC BY-SA 4.0 via Wikimedia Commons

The course

The 21K Buenos Aires circuit is urban asphalt, homologated by World Athletics, and starts and finishes at Avenida Figueroa Alcorta and Dorrego.

The course in short 2 lines
  • A certified urban circuit billed as America's fastest halfWorld Athletics homologated, billed as the fastest half marathon in America.
  • Three hours, with start waves from 8:00Waves from 8:03 to 8:30 by finishing time; 3 hours to finish.
Course notes 2 short reads on the course
Whole courseGeometryA certified urban circuit billed as America's fastest halfWorld Athletics homologated, billed as the fastest half marathon in America.

For the 2026 edition on 23 August, the organiser’s regulations describe an urban asphalt circuit homologated by World Athletics, with a sign at every kilometre. Start and finish were at Avenida Figueroa Alcorta and Dorrego. The organiser’s page calls it the fastest half marathon in America since 2009 and says the race broke the hour barrier in 2018.

Sourced

Whole courseTacticsThree hours, with start waves from 8:00Waves from 8:03 to 8:30 by finishing time; 3 hours to finish.

The 2026 regulations set the start at 8:00 and the end of the race at 11:00, with 3 hours 00 minutes as the official maximum time. Runners were released in waves by declared finishing time, from 8:03 for those under 1 hour 15 minutes to 8:30 for those over 2 hours 31 minutes.

Sourced

Race fuel

Energy gel
An energy gel sachet
Illustration · drag to turn

2 gels for Buenos Aires, plus 1 spare

Finish

One every 40 minutes, by the clock:

  1. km 7.3mile 4.6
  2. km 14.7mile 9.1

Our pick: SiS BETA Fuel gel, box of 6, strawberry and lime. 40 g of carbohydrate a gel, about twice a usual gel, from two kinds of sugar your body takes up side by side.

Easy to forget on race morning: pack them with your bib the night before.

Get it on Amazon

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In Canada the button opens GU Energy Gel, Salted Caramel, 24-pack, the best seller there.

Outside the Netherlands, Belgium, Germany, Austria and Switzerland, the UK and Ireland, Spain and Portugal, Italy, the rest of the EU and Canada the button opens GU Energy Gel, Chocolate Outrage, 24-pack on Amazon.com, the best seller there.

Anti-chafe
Compeed Anti-blister stick
Photo: Compeed

Compeed

Compeed anti-blister stick, 8 ml

Best selling on Amazon amazon.nl, read 2 Nov

An invisible layer before the start keeps seams, straps and shoes from rubbing skin raw.

Put it on before you leave for the start: heels and toes, inner thighs, under a bra or heart-rate strap.

Try it on a long run first, like everything you use on race day.

Get it on Amazon

We earn a small fee if you buy through these links. The price is the same.

Number belt
A race number belt
Illustration · drag to turn

Compressport Race Belt

Holds your bib without safety pins through your top, with loops for up to 8 gels.

Clip the bib on the night before, so it goes on with your shorts in the morning.

Keep the number on the front, where officials and photographers can see it.

Get it on Amazon

We earn a small fee if you buy through these links. The price is the same.

Electrolytes
A tube of electrolyte tablets
Illustration · drag to turn

SiS Hydro electrolyte tablets, tube of 20

One tablet in a bottle puts back some of the salt you sweat out.

One tablet in 500 ml of water in the hour before the start.

Only if you have used them in training: nothing new on race day.

Get it on Amazon

We earn a small fee if you buy through these links. The price is the same.

Blister plasters
Compeed Blister plasters, medium, 6
Photo: Compeed

Compeed

Compeed blister plasters, medium, 6

Best selling on Amazon amazon.nl, read 2 Nov

One in a pocket cushions a blister if one starts.

Put it on clean, dry skin and leave it until it comes off by itself.

Give a couple to whoever comes to cheer, so they are there at the km you need them.

Get it on Amazon

We earn a small fee if you buy through these links. The price is the same.
distance
21.1 km13.1 mi
cut-off
3:00 h

Trip

Getting a place

Entry through the organiser

Entry details on the organiser’s site →

The organiser, a third party. We take no entries and have no part in the race.

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