Abstract Route Types

To review previous posts on this subject:

  • A swim route is either natural (defined by geography) or artificial (defined by buoys).
  • A swim route is repeatable if it is both natural and enforced.
  • Repeatable routes are the gold standard for solo marathon swims and distance record attempts.

First, consider buoy routes: An infinite variety of course shapes are possible. This malleability makes them perfect for mass-participation events, efficient use of safety personnel, and specific-distance courses (such as 10 km or 2.4 miles).

In contrast, the natural routes are constrained by the shape of the body of water (which makes them repeatable). Further, there are only a few fundamental “route types” that can arise from any given aquatic geography. We will call these Abstract Route Types, and there are five of them.

1. Point-to-Point

”Here to there…”

A point-to-point is a continuous swim from one land location (start), across water, to a different land location (finish).

  • The route definition includes a start location, finish location, and any intermediate waypoints necessary to connect them by the shortest swimmable path.
  • The route distance is the sum of the straight-line segments connecting the start, finish, and intermediate waypoints.
  • Unless it is a channel swim (see next section), the start and finish should be unambiguous, well-defined locations such as a named beach. Use coordinates if there is any ambiguity.
one way route

One-way route: Flathead Lake, Montana. Somers to Polson. GPS track of Craig Lenning (2015).

Examples: Lake Tahoe (Camp Richardson to Incline Village), Swim the Suck (Tennessee River), Boston Light Swim.

1a. Channel Swim

”Shore to shore…”

A channel swim is a point-to-point swim between two distinct land masses (between two islands, or between an island and a “mainland”).

A channel swim is distinguished from a general point-to-point swim in two ways:

  • The route definition is typically a straight line without any intermediate waypoints.
  • The route distance is typically the minimum distance between the two land masses, regardless of the specific start and finish location.

For example, an English Channel swim is 20.5 statute miles, even if the swimmer begins in Folkestone and finishes in Wissant (a straight-line distance of nearly 25 miles).

Enforced point-to-point routes in lakes, bays, and rivers depend on starting and finishing at specific spots. Lake, bay, and river routes can be shortcut, but channel swims cannot.

channel swim route

Channel swim route. Isle of Man to Northern Ireland. GPS track of Triskelion relay (2017).

Examples: Any of the Oceans Seven swims. Alcatraz to San Francisco.

2. Multi-Way

”Out and back…”

A multi-way is a semi-continuous swim consisting of two or more consecutive swims of the same point-to-point route.

Each distinct part of a multi-way swim is called a “leg.” For a multi-way swim to be enforced and repeatable, the swimmer must clear the water (or touch land above water) at the end of each leg. Typically, the swimmer is allowed a maximum of 10 minutes on land before starting the next leg.

Multi-way swims are semi-continuous due to the necessity of touching land at each end (to enforce the route distance). The only fully continuous swim routes are point-to-points, circumnavigations, and island loops. If the swimmer breaks for longer than 10 minutes on land, it is a stage swim.

multi-way swim route

Two-way English Channel swim. GPS track of Sal Minty-Gravett (2016).

Examples: Any point-to-point swim (see previous examples) prefaced by “double,” “three-way,” etc.

3. Circumnavigation


A circumnavigation is a swim around an island.

  • The route distance is the shortest path around the island.
  • To ensure the stated route distance is the true minimum, the route waypoints should include the island’s most prominent points of land.
  • To ensure the route is enforced, the swimmer must clear the water (or touch land above water) at or beyond the start location.
  • The direction of the circumnavigation (clockwise or counter-clockwise) should always be specified, and are distinct routes.
circumnavigation route

Circumnavigation route: Swim around Santa Cruz Island, California. GPS track of Selkie & the Sirens relay (2017).

Examples: Manhattan Island Swim (20 Bridges), Around Anacapa, Mercer Island Marathon Swim.

4. Island Loop

Out, around, and back…

An island loop is a swim from one land mass, out and around an island, and returning to the first land mass.

Like circumnavigation routes, the direction of island loops (clockwise or counter-clockwise) should always be specified. Because the swimmer does not touch the island or complete a full circumnavigation, island loops are fully continuous swims.

island loop route

Island loop route. Round-Trip Angel Island. GPS track of Evan Morrison (2015).

Examples: Round-Trip Alcatraz (a.k.a. “Swim Around the Rock”) and Round-Trip Angel Island in San Francisco Bay; Swim Around Alligator Light (Florida Keys); loop around Robben Island from Cape Town (first swum by Theodore Yach in 2009), Charlotte Brynn’s loop around Ile Ronde from Newport in Lake Memphremagog; Sarah Thomas’ 104-mile loop in Lake Champlain around Gardiner Island VT from Rouses Point NY.

5. Combination

A combination route involves two distinct routes (point-to-point, multi-way, circumnavigation, or island loop) performed consecutively.

  • an “A-B-C” route is two consecutive point-to-point swims, with the finish location (“C”) being different than the start location (“A”).
  • a “lollipop” route is a circumnavigation swim done consecutively before or after a point-to-point swim.
combination swim route

Combination route. Anacapa lollipop swim. GPS track of Peter Hayden (2014).

Example: Jen Dutton’s Keuka Lake “A-B-C” swim in 2015.