The ship's maximum speed was warp two (Cochrane scale). The Horizon was capable of hauling loads of up to 30 tons and was commissioned in 2102. It is rumored that the inside of her warp core casing was autographed by Zefram Cochrane. (ENT: "Horizon")
- Information taken from a deleted scene edited out of "Fight or Flight". The scene can be found in the ENT Season 1 DVD.
In 2141, the Horizon encountered a group of Deltans. Travis Mayweather, who was fifteen at the time, described them as very attractive and very open. (ENT: "Bound") The Horizon once came under attack by Nausicaan pirates; it barely escaped in one piece. (ENT: "Fortunate Son")
In January 2153, the Horizon was attacked by the same pirates that attacked the ECS Constellation many weeks prior. However, thanks to Travis Mayweather's skills the ship was able to withstand the attack. (ENT: "Horizon")
Among the planets visited by the ECS Horizon include:
Although the capabilities of this vessel vastly limit its travel radius, it has been suggested that this vessel may be the Horizon that discovered the planet Sigma Iotia II in 2168. This is believed, in part, due to the fact that the dialog from "A Piece of the Action" (TOS) never clarified the origins of that Horizon, outside of being an Earth starship. Interestingly, this connection to TOS was not lost on the set decorators of Enterprise - in "Horizon," a hard bound copy of a book beginning with the title Chicago Gangs can be briefly glimpsed on a bookshelf in Travis' quarters aboard his old ship.