You can book through a cruise vacation with a stop in the country of Spain. But if you intend on traveling from USA to Spain; I do not know if there is such route. But if ever you are in Spain please do not miss to visit Tenerife.
Boat, train,or plane
It takes 12hrs
By Boat
Columbus left Spain in the Santa Maria, with the Pinta and the Niña alongside
Yes you can if you take a boat or a plane
no you must drive a car
Mostly north.
It depends where you live.
Yes, mostly during the Gilded Age during 1890-1903.
You need a valid passport only.
No, there is no through-river.
Preferably by sea. However, travel to Cuba from the US is not allowed.