Autobot City

Autobot City (also known as Autobot City: Earth) is a city established on Earth in some Generation 1 continuities. As well as being outfitted so that a large number of Autobots can live and work in comfort, the city can transform into a fortress as shields engage and weapons appear all over it. The transformation needs to be triggered by a series of bulky manual operations.

It first appeared in The Transformers: The Movie. Generally, it is linked to Metroplex in some way (a few pieces of fiction use the two names interchangeably).

Generation 1 cartoon
By the early twenty-first century, the Autobots' presence on Earth was sufficiently established that they had built their own high-tech Transformer-scale city in North America. It took major damage during a Decepticon attack in 2005. The city was repairable, though, and continued to operate for some time afterwards.

The internal computer was Teletraan II.

Metroplex transformed into a section of the city, being able to detach himself and become mobile when needed. The series usually showed white city-features for 'Metroplex' parts, and gold for parts of the main city.

Marvel UK Generation 1 comic
''Autobot City: Earth was completed in 2003, likely on the same site that Galvatron had built a superweapon to destroy Unicron in 1986 (putting it in or near Oregon). Both the Autobots and the governments of Earth had a hand in its contruction. Despite interference from Shockwave, the city opened on schedule and relations between Autobots and humans were strengthened.''

''It was attacked by the Quintessons in 2008, leaving many Autobots severely wounded and the city in terrible shape. The Quintessons were only drive off when Hot Rod activated the Transformer that made up the city's sentient core, Metroplex. (According to the story, the city needed a Transformer within it to be able to transform itself.) While successful, Metroplex's emergence only damaged the city further, and it was still in a state of disrepair the following year.''

Toys
No toy of Autobot City itself was ever released, though Metroplex was billed as the 'Autobot City' in packaging and promotion.