It isn't. There is no reason for having the camp that can't be bettered by other options available.

it was created in 1898

"Gitmo" is a term for the detention facility Guantanamo Bay. One can find more information about the facility by reading the Guantanamo Bay Wikipedia page.

the maximum prison at the guantanamo bay naval base in cuba?

No. Detainees are held without charge or reason - and are not even within U.S. jurisdiction when they are "arrested" - are tortured on an almost daily basis, and are deprived of human contact.