Commentary Inf IX 107-111

The protagonist shows his usual touristic interest in seeing the new 'sights' within this 'fortezza.' The word the poet chooses reminds us that we here behold a different aspect of hell. Once we see the even more imposing structures awaiting the travelers (Malebolge and the walled city of Cocytus), we have some sense of the import of the first 'built environment' of hell that we experience after that imposing gate described in the third canto, a sign that the sins punished within it are more offensive to God than those above.