How to read the desk

Formats we rank

• Trail 100 mile

  100M

  About 100 miles on trails and mountains — Western States, UTMB, Hardrock. Hours, not minutes.

• Trail 50–100K

  50–100K

  Shorter mountain ultras: 50 to 100 kilometers. More of a footrace than a 100-miler.

• Backyard

  Yards

  Last one standing. The same loop every hour until only one runner can start again.

• Road & timed

  Road

  Road ultras and races against the clock: Spartathlon, 24-hour, 48-hour, multi-day loops.

• Stage & expedition

  Stage

  Multi-day or huge-distance events — Cocodona 250, Tor des Géants, expeditions.

Words you will see

Yard · One hourly loop

In a backyard ultra, a yard is one loop of the course — usually 4.167 miles or 6.706 km — that every runner must finish inside the hour. Finish in time and you may start the next yard. Miss it and you are out.

Backyard ultra · Last one standing

A last-one-standing race. Everyone starts the same loop at the top of each hour. There is no fixed finish distance. The race ends when only one runner completes a loop nobody else does.

DNF · Did not finish

Did not finish. The runner started but left the course before the finish — injury, cutoff, or choosing to stop. In a backyard, stepping off or missing an hour is how almost everyone ends.

Cutoff · Must-be-there time

A time limit at an aid station or the finish. Arrive after the cutoff and you are pulled from the race. Backyard ultras have a hard one-hour cutoff every loop.

Aid station · Food, water, crew

A staffed stop on the course with water, food, and often medical help. Crews usually meet their runner here. On a map they mark the official checkpoints.

Trail 100 mile · 100M

A roughly 100-mile (160 km) race on trails and mountains — Western States, UTMB, Hardrock. Time is measured in hours, not minutes. The Kick Rocks 100M board ranks this format.

Trail 50–100K · 50–100K

Shorter mountain ultras: about 50 to 100 kilometers (31–62 miles). Faster and more of a footrace than a 100-miler. CCC, OCC, and many World Series races live here.

Road & timed · Road

Road ultras and races against the clock instead of a trail: Spartathlon (Athens to Sparta), 24-hour, 48-hour, and multi-day track or loop events.

Stage & expedition · Stage

Multi-day or huge-distance events that are more expedition than a single push — Cocodona 250, Tor des Géants, stage races across deserts or ranges.