No, no visa will be needed.
The EU is introducing a system equivalent to the US's ESTA. (Most) EU citizens may travel visa-free to the US but must register (and pay) on ESTA.
It will be the same for US citizens to travel to the EU.
The EU is introducing a system equivalent to the US's ESTA. (Most) EU citizens may travel visa-free to the US but must register (and pay) on ESTA.
It will be the same for US citizens to travel to the EU.
ESTA specifically allows people to travel visa-free.