The Slab is an enigma of geometric precision.
It's a wave that breaks in a left-handed direction in the Mayo area. An enormous, well... slab of rock - imagine a huge flat area of rock on a 6 or so degree tilt, maybe 70 feet long, sloping gently into the sea. It's walled by stout cliffs about 10-20 foot high.
The waves, as they approach, drain the water from the rock shelf as the wave stands up and heaves straight over into a flawless cylinder that fires down the line of the slab. It was anywhere between a foot and two foot deep in any area of your ride. There's some seaweed on the rocks but predominantly just rock. The flawless angle and shape of the sloping shelf is echoed by the wave - flawless perfection.
The take-off can be dangerous if you don't jump straight to your feet and set your line down the wave as failure to do so usually results in being washed rolling directly up rock leaving you high and dry. But if you make the take-off, and can manage to slow down so that you and the board sit right under where the wave is curling over you the sensation is incredible. Imagine skating inside a quickly revolving tin-can that cycles relentlessly faster (or so it seems) as you hurtle forward.
Now either the bend in the wave is either convex, in which case your ride ends as the wave face fades into deeper water or the angle of the wave is concave in which case the waves picks up speed, locking you in as you hurtle towards the cliff-face with no possible means of escape and usually you bail off the back of the board kicking it forward so as not to get sucked up and into the top over the wave and get driven into the slab with your board.
Very intense even when the wave is only two to three feet.
However the wave is at it best and most makable when it is four to six feet plus. Harrowing to say the least.
This is why, personal opinion of course, football and these other so-called 'contact' sports seem feeble in comparison.