Me too! In fact I've been there far more than twice, and wasn't aware of 420. A few years ago I had a stopover of several hours there between flights so I took a train to a large model railway shop an hour or so outside the city and spent a happy and productive time browsing. A few years previously, again with a long stopover between flights, I took the train into the city centre not realising it was the queen's birthday, and had a thoroughly enjoyable day watching the Dutch, all dressed in orange, celebrating with large quantities of alcohol. Now that Brexit has deprived me of my European citizenship I wonder whether it will be as easy in the future to leave the airport just to pop in to a bar or model railway shop on the spur of the moment.