I heard of this place, but I knew nothing about it, so I thought I would try it. I heard about this place. It seems like a good idea. The first one suggests only existence is known. There may have been no details. The second one gives a suggestion that some information was given. In practice they are likely used rather interchangeably.

that does make sense! thank u!

The difference between these two phrases....hmmmm. Of: more for a person or concrete thing. About: a topic. I have never heard of him! I haven't heard about that idea before. About means there is a larger area, or space, or context of idea being considered. "Have you heard about the (situation)?" Instead of: "Oh, you know, I have heard of Brad Pitt before, and I don't want to hear anything else about him." About means a wider topic. Of means a person or one thing.