Hi Carl, Sure, you can find the full definition in this publication: https://dggs.alaska.gov/pubs/id/31086. It's: -unquestioned eruption post-contact (1700 CE) -strongly suspected eruption since 1700 CE -persistent fumarole activity -significant volcanically sourced deformation -earthquake swarm with volcanic cause We used to call this "historically active" but we've updated our terminology in the past year. We're chatting about your website feature request. I'll get back to you on that one soon. Thanks! Abbey Nastan --------------------------------------------------- Could you please provide the definition of "recently active" from this page: https://avo.alaska.edu/volcano/ 10 years? 100 years? 500 years? Thank you.