otherwise, it’s going to be flooded with people.

[yi-ing]

Original sentence: Crowds become far larger after midday, so it’s best to get there as early as possible, because it’s going to be flooded with people.

Are these two sentences correct as well?

Crowds become far larger after midday, so it’s best to get there as early as possible, or it’s going to be flooded with people.

Crowds become far larger after midday, so it’s best to get there as early as possible; otherwise, it’s going to be flooded with people.

 

[Tarheel]

Perhaps:

It's best to get there as early as possible to avoid the crowds.

 

[yi-ing]

The second would be if the comma after 'possible' were a semi-colon.

Thank you Piscean. There is no comma after possible.
In my original post, there is ";" not ',' after possible.