FOSS4G 2017 Boston, USA
The annual FOSS4G conference is the largest global gathering focused on open source geospatial software. FOSS4G brings together developers, users, decision-makers and observers from a broad spectrum of organizations and fields of operation. Through six days of workshops, presentations, discussions, and cooperation, FOSS4G participants create effective and relevant geospatial products, standards, and protocols.
Find more info at http://2017.foss4g.org