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Miami Backyard Ultra

Name: Miami Backyard Ultra
Start: 2026-12-19
End: 2026-12-19
Location: Key Biscayne

Key Biscayne, Florida, United States

calendar_today 19 Dec, 2026

directions_run Running

language Official Website

sell $249.00

About the Event

CAME TO FIND OUT.

One 4.167-mile yard. Every hour. Until one remains.

Miami Backyard Ultra starts December 19, 2026 at 8:00 AM EST at Miami Marine Stadium / Virginia Key. The field is limited to 500 runners.

Maybe it is two yards. Maybe four. Farther than you have ever gone. Through the night. Fifty miles. One hundred. The final yard. Everyone starts the same yard under the same rules.

Complete each yard in less than one hour, recover in the time left, then start with the field at the next hourly bell. There are no late starts, skipped yards, pacers or personal aid during a yard. One runner must complete one more yard than everyone else to win. All other runners technically record a DNF, with completed yards as their official result.

Parking, packet pickup, basecamp, crew access and aid procedures will be published in the Athlete Guide before race weekend. Participant award details coming soon.

Full rules / FAQ

Races Offered

Backyard Ultra

Dec 19, 2026

straighten

Distance — Backyard Ultra

terrain

Type — Running

timer

08:00

sell

$249.00

Weather History

These values represent the 3-year monthly averages for December in Key Biscayne.

thermostat Temperature

19.1° / 24.8°

wb_sunny Feels like

18.2° / 24.5°

light_mode Avg sunshine hours

8h 27m

water_drop Avg rainfall

4.3 mm

ac_unit Avg snowfall

—

air Avg wind speed

14.6 km/h (Gentle breeze)

opacity Sweat loss rate

High

terrain Course conditions

Hard and dry surface

sunny Max UV Index

Low (2.4)

humidity_mid Humidity

73.2%

wb_twilight Sunrise

07:59

nightlight Sunset

18:33

About Key Biscayne

Learn more about the host city, Key Biscayne.

Key Biscayne is a village in Miami-Dade County, Florida, United States. Located on the island of Key Biscayne, the village is part of the Miami metropolitan area of South Florida. The population was 14,809 at the 2020 census, up from 12,344 in 2010.