Short answers, pulled from the story.
The British Library was legally created on the 2nd of July 1973 by the British Library Act. Before this date, the nation's most precious books and manuscripts were scattered across a dozen different buildings.
The British Library building was designed by architect Colin St John Wilson in collaboration with his wife MJ Long. It was officially opened by Queen Elizabeth II on the 25th of June 1998.
The bulk of the British Library's holdings are stored at the Boston Spa facility in Yorkshire. This site houses 87.5 million items in more than 140,000 bar-coded containers.
The British Library's entire website went down on the 28th of October 2023 due to a ransomware attack attributed to the group Rhysida. Services were disrupted for several weeks, with some outages persisting into 2024.
The British Library holds around 14 million books along with substantial holdings of manuscripts and items from multiple countries. It adds some three million items each year to its collections.