Phnom Tamao Zoo
The Phnom Tamao Zoo is a wildlife rescue center. PTWRC currently houses over 1,100 animals, which include 93 species of endangered and threatened animals (elephants, tigers, sun bears, pileated gibbons and many others). Please visit the following link to learn more about the zoo: http://www.wildlifealliance.org/where-we-work/cambodia-wildlife-rescue/care-for-rescued-wildlife/
There is a long road (off the main road) to get to the zoo. There are dozens of people, mostly older women and men lined up on either sides of the road, asking for money. Once in the zoo (similar in fashion to the temples, but definitely not to that extreme) are people selling all sorts food and drinks. The most persistent vendors are those selling coconuts to you to give to the animals.
Betel Nut Tours
We were able to get a private tour with Betel Nut Tours. They know the animals and they give you an excellent lunch. It was a fun ride getting there. Our jeep broke down, so we had to ride on top of a van Cambodian style. It was fun, but I'd probably wouldn't do it again. You see enough patients with TBI's and you'll get scared of everything! I promise I am not pulling this gibbons leg off, she likes to have her leg rubbed with pressure.