Is the zoo off limits for ccw due to something I am overlooking, such as being state owned(cannot tell from their webiste if it is or isnt), or selling beer or wine inside?  
If it is a state park that means I can carry on the grounds but not inside any of the buildings, correct?
Any knowledge will be much appreciated.

Thanks in advance

Why? Plan on taking out Mike "Tyson" the gorilla?

Back when I was Grassroots SC's merchant issues chairman,  I did some cautious inquiry and was informed that Riverbanks Zoo is a venture involving the City of Columbia and a private foundation. It's a gray area that I was never able to nail down without exposing my hand, so to speak.

The zoo is posted against CWP but I am told that it's not legally compliant.

Hence, there are two ways at looking at this:

If the zoo is private property and not legally posted (as I've been told) then it's probably OK

If the zoo is private property and alcohol is served there it is likely limited to a certain area of the zoo and you should avoid that area and I AM NOT A LAWYER.

If the zoo is municipal property you can legally carry on the grounds but not in any buildings. In any case if you are asked to leave, then leave.

I'm no longer involved with Grassroots SC but I'll do a few iinquiries and post anything I find.

I heard that one of the gorillas got out and attacked a food service worker on Friday and then went back to his cage, scarry shit!
Anyways, thanks for the info, and if you come across more  then let me know.  
I really hate these "gray areas" and try to stay legal at all times.

I don't see anything that would lead me to believe that alcohol is served in the zoo's restaurant.  My best guess is no.  The zoo is set up to handl private functions such as weddings but common sense is that they are private events.

If its posted, "not properly" or "properly", I don't carry.

I know that it's important to carry, and I don't like being without my weapon(s), but if a business owner says they don't want concealed carry on their property, I respect that.  Remembering, that I can avoid patronizing those places...

Here's your answer. This, from a friend who is a CWP instructor and former 12 year veteran of the Columbia Police Department:

"The Riverbanks Zoo is entirely publicly owned; therefore, CC in the buildings is prohibited.  I haven't been there in a long time, so I don't know about the signs.

It's not much fun to go to the zoo this time of year if you can't go into the buildings.  It's hot outdoors, and a fair amount of what there is to see is indoors."

just to try to help clear it up, i was just there Mother's Day i did not see any signs posted

Was Michelle Obama there? Did you see the Wookie exhibit?

Don't make Columbia's Mayor For Life Hizzonor The Bob Coble apologize for you too.

On second thought, Mayor Bob needs to suck the O-azz for more Spendulus Streetscaping funds.  Carry on.

Little known fact: Mayor Bob Coble's middle name is Massengill.  Columbia gets what it deserves for their constant re-electing of this recycled douchebag.  Chastity Bono won't need to grow her own dick, if she asks Mayor Bob he'll give her/him his... I hear it's in near new condition.