<p>Recent studies have shown agglomeration benefits in literary writing, yet the mechanisms behind the benefits remain unclear, specifically the role of proximity to other writers. Using annual data for 370 authors in the United Kingdom and Ireland, between 1725 and 1975, we combine locations, social ties, and publication outcomes including canonical status. We compare exposure to (i) all co-located authors and (ii) co-located personally connected authors, and we identify dense local “creative circles” as years in which an author co-locates with at least four of their documented personal connections. Panel regressions with author and year fixed effects show that, once we account for location type, general co-location does not raise overall publication quantity, whereas residence in London is associated with higher output. By contrast, co-location with personally connected peers significantly increases the likelihood of producing canonical works, with the largest effects in dense creative circles. These findings suggest that urban infrastructure scales production, while intensive peer interactions shape the creation of enduring, high-quality literature.</p>