Robert G.
Yelp
You could go to Buenos Aires, not see Cementerio de la Recoleta, and still have seen Buenos Aires. It might be like going to Los Angeles and not seeing the Walk of Fame on Hollywood Boulevard or Universal Studios, assuming you saw most of the other major things.
However, seeing Cementerio de la Recoleta is easy, it's interesting, and it's free. It is not far from from the center, in Barrio Norte and/or Recoleta, however it might be termed, and is next to Parque de la Recoleta, which is a great spot on weekends, humming with both Portenos and tourists alike.
It goes without saying that people come here to see the grave of Eva Person. In good taste, her grave is a modest one and is in the Duarte family mausoleum, which is her maiden name. A lot of the Buenos Aires tours also make it to this cemetery to see "Evita's" resting place. It's not near the entry, but it's not too far into the cemetery, either. You can follow the herd, trace it on a "trail map" in a tourist guide, or learn three words to ask any of the attendants or employees: "?Donde esta Evita?" ... which is sort of rude because she's no longer with us. However, they are actually helpful and not put out by this question, since they know that that one grave is what puts Cementerio de la Recoleta on the map ... at least as far as tourists are concerned.
If you do visit Cementerio de la Recoleta, be sure to walk around and see some of the other graves. Since people had to be affluent to be buried here, and even Eva Person's being laid to rest here was debated because of her less than stellar ancestral tree, the graves (mostly mausoleums) are a vulgar display of wealth owing to how lavish and ornate they are. Admittedly, it is very interesting. The other interesting thing is all the stray cats that live in the cemetery. I'd say they come a close second in making this cemetery a fascinating place. They are fairly tranquil, you don't see much in the way of cat fights, and you'd almost think THEY think they own the place. Most of them appear to be well fed, as I'm almost sure every eccentric in the neighborhood who is obsessed with cats might be feeding them.
Put this cemetery on your bucket list for your Buenos Aires trip. I am a fan, as in 4 stars, because I think I would go check it out every time I could visit this unique capital ... if not for Eva Peron's grave, then to see all the other tourists acting like tourists, obnoxious mausoleums I hadn't seen before, and, of course, the latest bumper crop of cats!