Introduced in the early 2270s, the K't'inga-class cruiser was considered one of the most powerful warships in the Klingon Defense Forces, even serving as a flagship of the Imperial Fleet for a time during the 2290s. (Star Trek: The Motion Picture; Star Trek VI: The Undiscovered Country)
K't'inga-class cruisers were in service as early as 2272, when the Epsilon IX station recorded the destruction of three K't'inga-class vessels by the V'Ger entity. (Star Trek: The Motion Picture) Starfleet's interest in the K't'inga-class cruiser was such that in 2285, the class of ship appeared in the Kobayashi Maru training scenario at Starfleet Academy. (Star Trek II: The Wrath of Khan)
For nearly a century, the K't'inga-class cruiser proved to be a rugged, sturdy design that saw continuous use. In that aspect they were much like their Federation counterparts the Excelsior-class and Miranda-class starships, whose usefulness outlived contemporaries such as the Constitution-class cruiser.
With marked improvements, these warships saw continuous use as front-line and border patrol ships throughout the Second Klingon-Federation War and the Dominion War of the early-2370s. (DS9: "The Way of the Warrior", "Soldiers of the Empire", "Call to Arms") They were not always the ship of choice for all missions, however, as more agile craft like the Klingon Bird-of-Prey were better suited for some tasks. (DS9: "Once ...