Piver 25 Trimaran (Mariner/Cruising 25)

Description

The Piver 25 Trimaran (most commonly the Mariner 25 or sometimes referred to as the Cruising 25) is one of Arthur Piver's popular trailable cruising trimarans from the mid-1960s. It was part of his lineup emphasizing amateur-friendly plywood/fiberglass construction, seaworthiness for coastal/offshore use, and trailering capability (beams often reduced to ~8 ft for road transport). This model fits between smaller day-sailers like the Nugget 24 (or Nugget Mark II) and larger cruisers like the Nimble 30. Piver promoted it as a "minimal full-cruising, trailable trimaran" — compact yet capable for extended voyages (with 2-person crew ideal for long trips), suitable for rivers, lakes, bays, or oceans. Many were home-built from his plans, with some professional or semi-pro builds. It shares the classic Piver traits: V-shaped amas for lift and stability, simple rigging, and a focus on lightweight performance with surfing potential in moderate-to-strong winds. Piver himself borrowed a similar 25 ft tri from a homebuilder in 1968 to attempt qualifying for the Observer Singlehanded Trans-Atlantic Race (OSTAR), but he disappeared at sea during that voyage — adding a poignant note to the design's history.