This study examines how geographic location affects the satisfaction of English language teachers participating in the innovative Teacher Activity Groups project. The project represents a pioneering example of technology-enhanced, cross-cultural collaboration between a Welsh institution, where English is the native language, and Vietnam, where English is taught as a foreign language. The six-month project was conducted entirely online, using digital platforms such as Zoom and Google Meet for interaction, fostering cooperative learning and problemsolving among 147 K-12 teachers. Employing a theoretical framework that draws upon the adult learning theory, the community of practice theory, and the zone of proximal development theory, this study offers a comprehensive evaluation of the Teacher Activity Groups project, focusing on five key levels of analysis: participants’ reactions, participants’ learning, organisation support and change, participants’ use of new knowledge and skills, and student learning outcomes. The questionnaire’s quantitative findings reveal notable differences in teacher satisfaction across urban, suburban and rural areas. Notably, suburban teachers expressed greater satisfaction in almost all measured categories. This disparity across different geographical areas highlights the importance of considering context-specific factors in the design and implementation of professional development initiatives like the Teacher Activity Groups project. Through its analysis, this study underscores the potential of cross-cultural, online collaborative projects in fostering professional development and suggests areas of focus for enhancing English language teaching and learning in different socio-educational contexts.