Constitution

Arguably the most famous class of explorer in history, the Constitutions include the original NCC-1701 Enterprise which perhaps not unsurprisingly was involved in the Zeroth Battle of Alpha Centauri during the "Crisis of Infinite Enterprises" temporal incident. The class has been retired from service.

Under development since the 2230s, the lead ships of the Constitution-class, the eponymous USS Constitution and USS Enterprise, entered service in 2245. These ships represented a radical advance in capability compared to the preceding Ranger-class heavy cruisers, and served the Federation well as both frontline capital ships and exploratory vessels throughout the mid-23rd century. Large and powerful enough to match the heaviest Klingon battlecruisers, but with state-of-the-art computer systems, laboratory suites, and accommodations, the Constitutions played a major role in defining the modern Starfleet concept of an 'explorer.'