Not all philosophy is equally impenetrable. Modern academic philosophy is very hard to read because it is entirely aimed at a graduate+ level academic audience. In contrast, classic philosophy was often aimed at a general(ish) audience. It can still be difficult, depending on the lucidity of the writer, and how different their cultural context was, but it doesn't require the same level of prior knowledge. Of course, the concepts themselves are still often difficult to wrap your head around, but that's the whole work of philosophy.
If you go back before the current era, you'll find that the primary sources in philosophy are often considerably more accessible than the commentaries. The commentaries tend to assume prior scholarship, and almost inevitably push their own assumptions and interpretations, which can muddy the waters rather than make them more clear.
Plato's work is all written to communicate directly with different segments of his audience. It isn't hard to read in a good translation, although the unfamiliar cultural context can be baffling at times (as can Plato's uncompromising Idealism). Taken together, his Republic and Symposium are the foundational key works of all Western philosophy. Descartes' Meditations are quite short and very clearly written. I personally dislike Hume, but he's easy to read (and has a wicked sense of humor) once you get used to the old fashioned style. The literary work by Sartre and Camus is compelling just as literature, in addition to its philosophical merits. Kierkegaard is more poetry than prose, if you can get past that, he's a good read. Lao Tzu is elliptical and aphoristic --that's apparently a core feature of the Chinese language --but not hard to read (in a good translation). Ecclesiastes is very accessible. (Conversely, Hegel and Wittgenstein and to a lesser extent Kant and Aristotle, are notoriously hard to read, while Confucius is obscured by an excess of culturally specific references.)
