Petrova Niva (Bulgarian: Петрова нива, "Peter's field") is a historic area in the Strandzha mountains of southeastern Bulgaria where, between 11 and 13 July 1903, a group of Bulgarian Internal Macedonian-Adrianople Revolutionary Organization (IMARO) delegates announced the outbreak of an anti-Ottoman uprising aimed at liberating southern Thrace from Ottoman rule and proclaimed the Strandzha Republic.