What is the subject of Catullus' poem 101?

The subject of Catullus' poem 101 is indeed the visit to his brother's grave. In this poem, Catullus expresses profound grief and sorrow over the death of his brother, reflecting on themes of loss and mourning. He articulates a personal farewell and pays homage to his brother's memory, underscoring the intensity of his feelings. The portrayal of visiting the grave highlights the emotional connection and the pain of separation, which is central to the piece.

The other options do not align with the poem's content or theme. While Catullus did write about love and relationships extensively, those themes are not the focus of poem 101. There are also no celebrations of a wedding or accounts related to traveling to Rome presented in this particular poem. Hence, the visitation to the grave encapsulates the intimate and sorrowful essence of Catullus' tribute to his brother, making it the correct subject of the work.