America is listed as one of free travel countries. As long as you apply for a passport from your country, you should be able to go to America and many other countries (if your country us in good standing with America) for no longer than 30 consecutive days.
Invites are not necessary, but you may want to call the center to ask about a reservation or purchasing a ticket in advance. I imagine their volume that day will be high and you don't want to risk not being admitted because of capacity.
Sorry Chib, nothing is free in America, but you are always welcomed. Maybe call the center and they might hook you up with a ticket. Other than that you have to pay.
Invite? No, you just show up and buy the ticket. About 20 USD.
I would call and ask about discounted tickets, there may be a special day that those are offered.
Call the center for civil rights museum or look them up for a invite.
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