It's a pretty nice beach right by UCSD, across Muir college.
They say that it's a world-renowned surf spot, but i think it's all right (I'm from Hawaii, so i'm spoiled by the warm water + hot chicks in bikinis).
Waves are usually better in the morning compared to afternoon.
There are several entrances to blacks (because it's a couple miles long until reaching Del Mar beach).
Contrary to popular belief, the beach itself is not a nudist beach; there's a designated part where being nude is legal.
me - 'ey, let's go surfing at blacks beach this afternoon
my friend - naww man, waves are better in the morning.
me - fu, it's fuking cold in the morning.
My friend - dude, i surf butt naked today at blacks!
me - wtf? i have never seen anyone do that
my friend - at the nudist part mang.
me - oh~. i'll try it later when it gets warm.