The jungles were on the lower levels, while the cities and living areas were on upper levels. Each herdship measured 1,000 meters in diameter, and was designed to contain a complete and living ecosystem. A pilot and co-pilot maintained the herdship's systems, supported by a crew of up to 3,000 Ithorian workers dedicated to the herdship's upkeep. A herdship could accommodate up to 10,000 individual Ithorians, as well as up to 20,000 metric tons of cargo.
The spacefaring herdships were based on the earlier herd-cities. Because these ships traveled throughout the galaxy, most were armed with twenty laser cannons and four tractor beam projectors distributed around the herdship's hull for defensive purposes. They were nearly identical in appearance to the herd-cities, such as the Tafanda Bay, but were enclosed to allow space travel.
Herdships were built in at least three known classes, the peaceful, cruiseship-like Manollium-class Herdship, the Shamarok-class Herdship, and the Sky Yards-class Herdship, built exclusively by the Ithorians themselves.
The spacefaring herdships were based on the herd-cities of Ithor, floating cities built once the Ithorians had achieved repulsorlift technology, to ensure that Ithor would never be despoiled. In the center of one herdship was the Dome of the Mother Jungle.
Individual herdships were sent from Ithor on a specific course and schedule, although it was up to the Ithorian pilot and his herd to determine their exact destinations. Each herdship returned to Ithor at a pre-arranged time known as a Herd Meet. After the destruction of Ithor by the Yuuzhan Vong, the herdships were the only reminders of Ithor's jungles to remain, making them more sacred to the Ithorian people.
As the herdships traveled around the galaxy, many planets would look forward to their arrival. Native species would eagerly trade with the Ithorians for whatever exotic wares they had brought with them. Some herdships included the Errant Trader, Ithor Wanderer, and Mother Ithor.