I am planning a four month research trip to the EU next year and will be visiting Sweden, France and other countries. I know a visa is required for visits of more than 90 days to one EU country. I'm wondering that even though I will be in no country for more than 50-60 days, I will be in the EU for approximately 110-120 days. Do I need to obtain a visa? Will multiple visas be required? Should I arrive and leave from the same country and obtain a visa for that country?