Complex sentence: The building was initially a post office with other government services; until the 2011 Christchurch earthquake, it was a Visitor Information Centre, but has since been inaccessible, as access for the public to the central city has been removed.
Split into simpler sentences: The building was initially a post office with other government services. Until the 2011 Christchurch earthquake, it was a Visitor Information Centre but has since been inaccessible, as access for the public to the central city has been removed.