Consider a random article about the 1190s, like [[da:1190'erne]]. Follow the interwiki links from that one. Follow te interwiki links from the newly found articles. Wonder how you ended up back af dawiki, but this time at the year 1190.
There is something rotten, not just in the state of denmark, but in a lot of the wikipedia articles about years and decades. I've made a simplified interwiki graph, http://wegge.dk/interwiki-1190.png. Be warned that it's a 13522 x 309 png image. The graph clearly shows that a lot of wikipedias have a path from their respective decade article, via [[he:1190]], back to the same wikipedias year article. This is not the only decade showing the problem, so it's not easy to fix. Given the the large number of wikipedias involved, it's too large a task to perform by hand, and I'm also afraid that before one such loop has been fixed, one or more iw bots will start spreading the problem again.
So does anyone have an idea about how to solve this mess by bot?