Apparently it looked like a lion's head when the first explorers arrived from the sea? It is a good walk up to the top, but we chose to walk around it, ending near where we parked.
It was about an hour's hike, stopping along the way to admire the view over Cape Town city and the coastline and the rest of the mountain as it disappears towards Cape Point. You get a good idea of the layout of the city and peninsula.
Many locals hike to the top after work or on moonlit nights. Do it!!
Oh yes, it is very safe but don't let valuables lay around in your car.