LOL I haven't heard about it being shut down either! Considering I live only a few blocks away from a station, I probably would've heard? It's not as an extensive system as London or Paris etc, but the metro most certainly is your best bet to get from the concerts' stadium to the centre of the city.

And... Amsterdam isn't as dangerous as people tell you it is. Not even the red light district - it's actually one of the areas where you can be sure there's always a lot of crowd and a lot of police on the streets. Same goes for Central Station actually. Hell, I never felt unsafe in the city, walking the streets alone at night .