All the questions (and other websites) about visiting Romania are confusing. But Romania has published a list of countries whose citizens do not need a visa, and USA is one. So, it seems that I do not need any visa for Romania, and I can ignore all the stuff about going there with a Schengen visa and only staying five days.
But again, this is confusing—have I got it right?
(update): well, the comments and answers eased my mind until I read
Should my first trip be to the country which issued my Schengen Visa?
and
Can I enter Romania based on unused multiple entry Schengen visa?
Now I am confused again. I entered Spain 5 April 2016 and am scheduled to fly into Romania 1 July 2016. That's four days short of ninety in Schengen. Plans are to spend more than four days in Romania. One or more of the answers in the above questions makes it sound like Romania will count the eighty-some days already used. I have no visa other than the stamp the Spanish guy made without even looking at any other pages in my passport.