[2] The Library is the permanent home to the Brian Boru harp, a national symbol of Ireland, as well as a copy of the 1916 Proclamation of the Irish Republic and the Book of Kells.

[10] Patrick Wyse Jackson, curator of the Geological Museum at Trinity, assessed the Old Library in 1993, and made the following observations:

The lower storey is built of muddy, well-bedded Calp Limestone, cut into regular rusticated ashlar blocks, which were quarried at Palmerstown...

The Calp has weathered to a pleasant, warm, brownish colour which contrasts well with the grey Ballyknockan Granite of the upper storeys.

Originally these levels were faced with white St Bees Sandstone from Whitehaven in Cumbria, but this disintegrated quickly and all but the carved cornice was replaced.

By the 1850s the room had to be expanded as the shelves were filled due to the fact that the Library had been given permission to obtain a free copy of every book that had been published in Ireland and Britain.

[16] In November 2020, Trinity College announced the addition of four marble busts featuring female scholars: Rosalind Franklin, Ada Lovelace, Augusta Gregory, and Mary Wollstonecraft.

[16] Beginning in 2022, the Long Room will be closed to the public as Trinity librarians undergo a €90m restoration project, utilizing €25m of government funding.

However, Lucasfilm denied that the Long Room was the basis for the Jedi archives, and officials from Trinity College Library decided not to take any legal action.