"There isn't anyone on that ship we can help anymore."
Arctic One was the designation for a United Earth Arctic One-type transport that was in service diring the mid-22nd century. In 2153, this starship was assigned to the A-6 excavation team, an Arctic Archaeology Team, a branch of the Earth Sciences Institute, for an exploration of Earth's Arctic Circle.
During their exploration of the Arctic Circle, the A-6 team discovered a craft of unknown origin. As they investigated the crashed vehicle and its crew, later identified as Borg drones, the nine members of the team, along with their ship, were assimilated into the Borg Collective. The new drones then attempted a journey in Arctic One to the Collective's territory in the distant Delta Quadrant. While not normally armed with weapons, the Borg-assimilated Arctic One had developed cutting beams and proton weapons. Its top speed was also increased to warp 3.9.
En route, the ship attacked a Tarkalean freighter, which sent out a distress call asking for assistance. The United Earth starship Enterprise NX-01, captained by Jonathan Archer, arrived to help the Tarkaleans. Archer ordered the assimilated transport to stop its attack or be fired upon, to which the transport fired proton bursts at the starship. Enterprise returned fire with its phase cannons, disabling the transport's weapons. Arctic One then retreated at warp while Enterprise sent an away team to help the survivors.
Additional Borg modifications
Arctic One was later intercepted by Enterprise, now considerably transformed and upgraded even further with its maximum speed increased to warp 4.8, its mass increased by three percent, and its defensive systems improved. The transport dropped out of warp before sending an activation sequence which disabled Enterprise's weapons and warp drive. The transport closed in and attacked Enterprise, critically damaging her hull before sending six drones onto the starship. Captain Archer and Lieutenant Malcolm Reed, the armory officer, then beamed aboard the transport and eventually destroyed the EPS manifold, disabling the transport's systems.
After Archer determined that there was no way to help the assimilated crew members, he decided to destroy the transport. Arctic One tried to lock weapons again but was destroyed by Enterprise, using four spatial torpedoes and a phase cannon blast. Nonetheless, before the ship was destroyed, the drones successfully transmitted a subspace message to the Delta Quadrant that included Earth's location. (ENT: "Regeneration")
Arctic One, in its initial form and its later "Borgified" appearance, was designed and illustrated by John Eaves. Eaves recalled "My job on this one was to create an Arctic exploration vessel that makes the discovery and later becomes Borgified. The first sketch is high profile vessel that I thought when Borged could form a cube. This idea was passed on and the second sketch got the approval. The ship is lightly based on a stylized snow mobile. Once Borged, it goes thru a variety of changes and this second sketch try’s to convey on of the stages of coverage. Pierre over at Eden modeled this one(...)"  Views of the model and design sketches of the ship can be found here and here.
In the writer's commentary for "Regeneration" on the ENT Season 2 DVD, the episode's writers revealed that the reason that the ship's mass kept increasing was due to an early concept for the episode where the ship would have eventually evolved into a Borg sphere, implying that the Borg don't have traditional shipyards, but instead take the ships that they attack and transform them into commonly-known Borg vessels. This concept was rejected in the final script, however. (Star Trek: The Official Starships Collection, issue 99, p. 16)