Well, I can tell you with a bit of AI helping me, I was able to figure out that there is a rightful cost for you to attend a zoological garden and see all the fauna that is there. If you have not attended a zoo for a long time, get ready for a sticker shock. Inflation and increasing costs have made going to the zoo as a pastime for familes to be quite unaffordable. I know, for some of you that would like to see the nature of RL animals at the zoo or even a wildlife sanctuary, it may be imparative to go to one to see their morphology, physiology/anatomy, and even some behavior towards humans if they are friendly or not.

It is going to be important that if you are with a group or if you belong to an association that is government-funded, you could get a discount, or lucky- have FREE ADMISSION. Lucky for me with my mother being with a retirement agency and that there has been a fair for retired folk for the county, she, along with me have free admission- and the city has paid for the funds.

THERE ARE A FEW PLACES IN AMERICA WHERE ADMISSION TO THE ZOO IS COMPLETELY FREE. Examples: Henry Vilas Zoo in Madison Wisconsin: www.henryvilaszoo.gov/ And the Washington D.C. Smithsonian National Zoo: https://nationalzoo.si.edu/

If you do not have that luxury however, yes, you have to dig in your savings account to enter. Of course, from what I studied, some zoos have state-of-the-art exhibits, and some have a lot more animals than others; even some zoos are world-renowned, and are keeping their recognition while being a part of the Association of Zoos and Aquariums ( www.aza.org/ ) (Or the WORLD Association of Zoos and Aquariums [ www.waza.org/ ]).

Of course, you will have to factor in parking, but sometimes, one will use the bus or even rail transit to get to these points of interest, so I'm not including these in the cost. However, if you do your research, and go at the off-peak hours, days of the week or seasons, you will have savings. So what I would recommend, do NOT go in the summer if you are saving money. Do not go on the weekends as now many zoos are ramping up prices for weekends since more are free to attend. Try to be in the morning admission or late evening before closing if you are able to have extended times into the night to see animals in action to see if you can save. And too, as there are advanced ticketing for admission, go for weeks in advance to get the best price to get in. Also look for zoo memberships or library/museum programs to have more discounts. And if you are a tourist, look for bundles at their chamber of commerce or visitor center fo discounts a-plenty if you go to many places of interest.

Now you want to get the mean price of the best priced zoos? I was able to get most in my home state California, but I did branch out-keep in mind that the prices listed are of general admission, which would be from perhaps 16ish to possibly 62 or what they say is considered a senior citizen on their admission tables.
If you are in the Northern California area and want to visit, the San Francisco-Oakland-San Jose-Sacramento-Monterey Megapolis (I will at some point nickname it the Capitol Corridor like the Amtrak Train: www.capitolcorridor.org/ since from 1850 to 1855, the capital of Califronia has been in this megapolis and moved MANY times.), you will see that the admission costs vare WIDELY. For Sacramento's small 14.3 acre zoo in mind, accessibility; and it's plan-ahead pricing, it is $16: www.saczoo.org/ .
The extreme example is Monterey's zoo which is also called, Wild Things Ranch- they have many acres, but the place is also used for scenery for motion pictures, and some of the animals there are in movies. Also, they do make the animal experience more intimate-attendees can go hands-on with the fauna. This will make the workers have more training, and there would be insurance involved. SO, expect the cost of admission to be more than double the cost of Sac Zoo-$37.75!: (The location is actually in Salinas, and is no way related to the renowned Monterey Bay Aquarium:) www.montereyzoo.org/

Now do compare with these in the SF Bay Area proper:

San Francisco: (WEEKDAY) $29; Oakland: $20; Happy Hollow (San Jose-this is also a park included): $22.
For these they do have other incentives-Oakland and SF are bigger than Sac, however, SF's has other amenities and missions that make the cost go higher-I did see one there a long time ago, and it was live feeding of the big cats. Oakland is just viewing, and Happy Hollow has less animals, but there is the park, but there is more hands-on experiences, and usually, the exotic animals are more friendly towards humans-therefore, there is insurance, and there's the extra $2 tacked on compared to what Oakland has. BUT for Oakland, they have expanded their land recently and have a gondola-it takes you to a native American animal exhibit. If you were to visit a zoo here in my metro area, I could say Oakland, but you could go for SF and Sac as well.

Now enough of the Capitol Corridor zoos-there are more, of course! It is not possible to get ALL zoos in the USA, so there will have to be a sample. To go back to how renowned the zoo is, and its purpose, you will have to see the that it will be REALLY expensive to go to the San Diego Zoo... $72-THIS IS FOR A ONE DAY PASS!!: https://zoo.sandiegozoo.org/ (This is not the SD Zoo Safari Park, but the price is nearly the same: https://sdzsafaripark.org/ ) Compare that to the frugally good Seattle Woodland Park Zoo at $12.95 off-peak WELL IN ADVANCE ADMISSION IF YOU BUY ONLINE: www.zoo.org/ (However, you will encounter at $19.95 very likely. )

So if it is that you will have to pay, I did have 25 other zoos that I picked to get the statistics needed to have you see the reasonable price of zoos that you can go to. It can help you in planning for future visits. I got data from Honolulu, Atlanta, Miami, Chicago, New York Bronx, Los Angeles, Tampa (QUITE EXPENSIVE!), Jacksonville, Milwaukee, Philadelphia, Nashville and then some along with the Capital Corridor zoos I listed. Yes, I did include the Smithsonian and Henry Vilas zoos as well despite free.

SAN DIEGO IS THE OUTLIER IF TAKING STANDARD DEVIATION.

For this as that zoo is in my sample of 26, the most expensive zoo in the USA, there are 2 data studies, and they are similar:

WITH SD ZOO INCLUDED (26 zoos):

Average:$25.86
Median:$22.00
Standard Deviation:$14.67

WITHOUT INCLUDING SD ZOO (25 zoos):

Average:$22.34
Median:$22.00
Standard Deviation: $10.63

SO~~
As it would be a sample of 25/26, it is a strong data set for overall what a US zoo cost would be- median holds strong at $22, but from the two averages, one can say $22-25 is a good price for today's world. Anything less is a bargain for base general admission.

For the aquariums however....

because of the cost of overhead and once can expect constant filtration of water, you would expect them to be more expensive to see. In just a size of 4 as in the Capital Corridor aquaria, it is a WIDE range- Monterey Bay is $65: www.montereybayaquarium.org/ (YIKES.) while SF's Pier 39 Aquarium of the Bay is $28.25: www.aquariumofthebay.org/ (I did not include Steinheart Aquarium as it is part of the whole package of the California Academy of Sciences there: www.calacademy.org/ ). I did also include Georgia Aquarium in Atlanta as $48.99: www.georgiaaquarium.org/ and National Aquarium in Baltimore at $49.95: https://aqua.org/ .

THESE ARE THE RESULTS (4 aquaria):

Average:$48.05
Median:$49.47
Standard Deviation:$13.08

So this is what you are expecting if you are going to see such animals face-to-face live. Get ready to have your money shelled out for seeing animals in the air, land and sea. But yes, for all you furry artists, it's best that you can see them on TV documentaries or on YouTube....

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