Marlin

Marlin is a Creature series swim: 15 km in Distance Lock — each counted swim must land in the 3–4 km band. Fast animal, narrow corridor: the billfish line on the board.

Distance Lock, fixed 15 km total. Every swim that counts must fall between 3 km and 4 km (inclusive of the band rules in the Rulebook). Scoring follows the mechanic once work is verified.

Clock (UTC). Open from 00:00 on 1 December through 23:59 on 20 December. Only swims published to Marlin in that span count.

After the period ends. 20 December closes the live phase; Results out follows later.

Fifteen kilometres only from sessions that fit the corridor. Miss the band and the swim does not build the total. Dolphin (30 km Multirun) overlaps the same December stretch; Snake Island opens mid-month.

Session design — Plan each swim inside 3–4 km, not “close enough”.
Pace the total — How many band-legal swims you need to reach fifteen kilometres before 20 December.
Enter vs stay out — A locked Creature line, or leave the marlin off your card.

A completed 15 km Distance Lock is a precision Creature mark. At Results out the race locks; until then provisional standings may move.

Get a race entry and start recording your workouts - it's that simple!

Any reliable apps and devices work: Strava, Garmin, Suunto, Apple Watch, and more.

No, participation is fully online - you can swim anywhere, whenever it suits you.

There's no strict minimum or maximum - anyone can join if their health allows.

Sure! Create your own team or join an existing one - it's more fun and motivating together.

Strava is a training log. URX is a competitive virtual swimming league: you enter an official race, swim in your own pool or open water, and publish a verified activity so the result counts toward standings and medals.

No. URX races are virtual: you swim in your own pool or open water during the race window. There is no venue or city start-line requirement.

The race starts on December 1 and runs until December 20 - don't miss your start!

Conditions

Participants & Level Matrix

Competitors' Strength

Level Matrix

Strongest participants

Context

X-Medal race

Race registration Marlin

Entry

Entry + Medal

FAQ