A Ring-terzanelle is a variation on the Terzanelle. Terzanelles were invented by poet Lewis Turco in the 1960s, and I discovered that form around 2007. I wrote several conventional Terzanelles, but found myself wanting to shape the form into something more my own, and more suited to my preference for narrative poetry.
Like the Terzanelle, a ring-terzanelle consists of a series of tercets where the middle line of each tercet is repeated as the last line of the next. Unlike the Terzanelle, it is of unbounded length.
The key feature that makes it a Ring-Terzanelle is the ending, where the final tercet is identical to the first. This means that the middle line of the next-to-last tercet is the last line of the first tercet.
Because of this cyclic structure, Ring-terzanelles make for interesting narrative poems. The repeated lines create a very strict pacing, and recontextualizing each one creates pressure to keep moving forward. The repetition in the final verse gives a chance to reflect on how far the poet and reader have come, as the opening lines are now recontextualized by everything that came after them. Sometimes this takes on an entirely new meaning, as in Beatrice's Rose, while other times it emphasizes the things that have not changed, as in Beloved I Would Write.