Few things tickle the interest of watchmakers like tourbillons do, so imagine what double tourbillon watches do to them. But the little whirlwind of minute metal components and springs wasn’t born out of vanity; it was designed as a mechanical solution to quite a perplexing problem at that time.

Way back before 1795, when wristwatches were still a concept unbeknownst to man, pocket watches were many gentlemen’s timekeeping tool of choice, and they either sat vertical in pockets or horizontal on desks. This caused an uneven distribution of gravitational forces and friction within the movement of the watch, eventually causing damage.

To solve this conundrum, French-Swiss watchmaker Abraham-Louis Breguet mounted the escapement and balance wheel in a rotating cage to negate the effects of gravity when the timepiece was placed in fixed positions for prolonged periods of time. This not only increased its accuracy, but also reduced wear and tear within.

However, unless you’re living the fantasy of being on Downtown Abbey, you’re more likely to own a wristwatch now, which means few timepieces actually spend their time exclusively vertically or horizontally. Like many complications, the tourbillon has evolved from being a technical solution to a show-off of watchmaking virtuosity. It wasn’t long before the single tourbillon started becoming “mainstream”, and so the horological hotshots started outdoing each other by doubling the stakes with two tourbillons instead.

Besides rotating at different speeds and offering higher accuracy, double tourbillon watches are often also highly fascinating in their sheer complexity. Here are five of the best in the market now.