Joggins, Nova Scotia, was one of the first places in North America where coal was mined. Dendrochronological methods were employed to date timber pit props preserved within relic coal mine workings on the closely adjacent Fundy and Dirty seams. These remains comprise a system of "openings" that represent formerly underground mines, now exposed by cliff retreat. Of the seventy-three samples collected, forty-eight were successfully cross-dated into floating chronologies and then compared against a local red spruce (Picea rubens) master chronology, thereby establishing the year in which each individual sample was cut as a live tree where bark was present. Results indicate cutting dates of 1849-1875, which are generally consistent with archival records of mining activity.