More unexpected XXX: Amsterdam traffic pillars

BoingBoing reader Morgan W. says,

There are pillars like these all over Amsterdam. When I visited the tour guide said they served as warnings to ships docking there– the X's stand for fire, flood nd black death (pestilence). This website claims it refers to St. Andew's cross (which is the flag of Scotland and one of the flags unionized in the Jack along with St. George's red cross and Ireland's red X). It was originally X X X not XXX and appears on the Amsterdam coat-of-arms vertically, but Amsterdam's flag has it the naughty way. This Wikipedia entry translates the coat of arms' motto as "Valiant, Resolute, Merciful."

Link.

Previously:
BB readers: XXX root beer, XXXX beer, Guber burgers
Yet another '50s kitsch restaurant called "XXX"

Reader comment: Chris Kawalek says,

Many of Amsterdam's benches were inlayed with an interesting juxtaposition of the XXX and Chess boards. Here is a picture I took a couple of years ago: Link. When I was there we were told that since 1947 the XXX has represented or was supposed to represent the three moral virtues: Compassion, Resolution, and Heroism.

Reader comment: dersk says,

They're called "Amsterdammertjes" – more or less translates to "little Amsterdammers". If you'd like a vaguely phallic traffic barrier, the city does sell them to groups and individuals. The crosses are the 'Andreaskruisen', after the apostle Andreas who was crucified on such a cross. So the St. Andrew connection is correct, and they do in fact stand for the three 'curses' of the city – fire, flood, and plague. The Compassion, Resolution, and Heroism thing is the motto of the city, and appears in the overall coat of arms of the city.

And, incidentally, amsterdammertjes are usually just short enough not to be seen out of one's rear view mirror, and leave nice purple scrapes on car doors.