Zipline

From Wikitroid, the Metroid wiki

A Zipline is a transportation device that appears in Metroid Prime 3: Corruption on the planet Elysia. They are used by grabbing onto one of the line's ends with the Grapple Swing and swinging along the line. The Arm Cannon is still usable during the ride, making this gameplay segment into something of an on-rails shooter (quite literally, as well).

Similar devices were also found on another Chozo home, Zebes, in Metroid Zero Mission, however these required only a free hand to ride.

[edit] Logbook entry

Metroid Prime 3: Corruption: "Zipline Cables were designed as a transit system between pods on SkyTown. Connect and hold onto the cable by pressing and holding Z while targeting the Grapple Point at either end."