In Star Trek Beyond, the massive Federation starbase visited by the Enterprise crew is Yorktown.
Yorktown is introduced as a vast, technologically advanced space station and one of the Federation’s major frontier outposts. Its distinctive design includes interconnected habitats and structures arranged around a central spherical hub, creating a memorable setting unlike the conventional starbases seen in earlier Star Trek films.
The USS Enterprise arrives at Yorktown after completing a diplomatic mission. Captain James T. Kirk and his crew are then assigned to respond to a distress call from the nearby planet Altamid. The Enterprise is attacked and destroyed during that mission, leaving the crew stranded.
Yorktown is sometimes confused with Deep Space Nine, another famous Star Trek space station. Deep Space Nine is a Cardassian-built station featured primarily in the television series Star Trek: Deep Space Nine, whereas Yorktown was created specifically for the 2016 film. The station also appears again at the end of the film, serving as a refuge after the crew’s return.