This is very close to what it looks like, almost identical except the cluster of little bits in the fruit. The photo's of that tree show a wavy pattern, this one has a bubble pattern...kind of like the blackberry. It's also full of milky white juice. Looks like milk. I couldn't find any reference on the net of the Cudrania tricuspidata having this milky white stuff inside. Any ideas? Anyone? I'm just dying to know for sure what this is :). Thanks everyone! Here is a link that might be useful:

Farm...WOW, thats alott of figuring.And a research project in it self. I'm assuming that when you ask where you can buy some...your meaning citrus trees? Harris citrus,Acorn Springs,Fourwind growers,Briteleaf ect..ect..ect..these are also mail order citrus nurserys.But depending on where you live you can go usually in the early spring and buy them. Sometimes places like even Home Depot has them for sale. And as far as weight & the largest of all,you do the math and the research, this would be a good study for you to do if your interested in growing citrus.I can probably name a few here,My guess for Limes would be the Bearss lime,and Lemon would be the Ponderosa,Orange would possibly be the Washington Navel...as for weight I'm stumped here! Like I said before,this is certainly a research project.LOL! Good luck,***Suzanne

Harpephyllum caffrum?

Right. Going on the opposite foliage and the shape of the fruit I wondered about something in the Myrtaceae. I found Eugenia myrcianthes. Info. here https://www.smgrowers.com/info/Eugenia_myrcianthesOrpet.asp In fact the picture in that link looks almost as if it’s the same tree as in the OP except it now appears to have been unsympathetically given half a bowl haircut. Ronald, if you are still there, what do you think? If it is the same location then it’s a good example of how important it is to give as much info. as possible. Googling the name of the park and ‘tree’ would have got that reference very quickly.