Are reservations needed or advisable?

You can buy it at the place or reserve it if you don't like lines

Tickets are required, you can buy them at the entrance. Your ticket will have the time stamped on it as to when you will enter. Our wait wasn't lengthy even through it was crowded due to holiday weekend.

Reservations are not required.

Dont need reservations

They are needed but you can pick them up at the base of the Tower