What is the fine-grained topic of the following text: Having left their dying planet behind, this space metropolis, along with its inhabitants, has been moving towards the distant, ghost-like Evacuation Point for the past 400 years, where the descendants of the once great people hope to start over the history of mankind. Only return the topic.
A space metropolis and its inhabitants journeying towards a designated Evacuation Point to restart mankind's history after their planet's demise.