Most wonders, both natural and man-made ones, are either fully intuitive or easy to explain. We look at waterfalls and geysers or into caves, and we immediately know why they are there. We see paintings and statues, or even such bizarre objects as a silver nose in a museum, and a couple of sentences is enough to clarify what they are about. Talking of museums, most of them are about exhibits. However, there are exceptions to either rule, and one such exception is to both rules, at the same time.
There is a clock in a room located in a tower at Copenhagen City Hall. The room is big enough to host a full-fledged museum of a modest size, yet the clock in question is the only object there. It wouldn't be too far-fetched to call it the "only exhibit" either because that clock is truly one of a kind. It's not for nothing that it is called the "World Clock". To quote the Atlas Obscura, "this gilded horological masterwork is geared to calculate global times and dates, and planetary positions with remarkable precision. And, as long as it continues to be wound once every week, it will continue to display this information for the next 2,500 years". The article goes on to provide very detailed information about when and how that clock was conceived, created and installed, but both that and readily available description of how the clock functions (multilingual technical texts and drawings are all over the room) take a back seat to one's immediate perception.
A spacious room, flooded with sunshine, immediately reminds of a temple of some sort - in this case, a Temple of Science. The divine resident of that temple is very complex, and it takes up a lot of space - yet, being fully symmertric and elegant, it doesn't strike as bulky. There are plenty of exposed shiny little parts - tubes, springs, even solid metal blocks - that create a sense of harmony almost too perfect to be real. One can't help thinking of a fairy-tale and, maybe, even looking for a little boy (and there is more than enough space for a little boy inside the clock!) trying to spell "Eternity". There is none. The clock keeps... no, not ticking, as the room is eerily quiet, but working like...well, clockwork! Every 100 years it falls behind by exactly 1 second - and it seems that Eternity has found its way into that room even without Kai...