We just went directly to the park, buy the tickets for that day. No reservations
You have to book a tour to go onto the island. So yea you would have to make reservations.
In order to view the Pedestal area of the Statue, you'd need to either prepay online or arrive early in the morning. Tickets for the Statue itself must be bought six months in advance. Tickets for Ellis Island can be purchased at any time. Grounds only tickets give you full walk around access, but no access to the Statue.
Reservations are needed
If you reserve it would be easy to board the ferry or will have to stand in a separate line to purchase the tickets. If you reserve it is directly security check which is near to the ferry.
If you just want to see Ellis Island you can park at Liberty State Park in NJ and walk over a land bridge. Or, you need to make a reservation on the ferry to go from Battery Park in NY.
The reservation line move faster, I would say thats the only reason to do it
I guess it is possible to book online, but what I did was that I bought the hop in hop out bus and the package that I chose had the ellis island. there is similar packages for different bus ride companies and different prices as well.
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