The Transmilenio is Bogotá's answer to the Medellín Metro, and while it isn't as elegant and efficient as a proper metropolitan railway, it does a pretty good job of shifting people round the capital. Instead of using trains, the Transmilenio runs on buses that have dedicated lanes down the centre of Bogotá's main roads, and most of the time this means that the buses run smoothly (though they still have to stop at traffic lights and can get a bit stuck in particularly heavy traffic, so it isn't perfect).
Unfortunately, the Transmilenio is an almost unfathomable system for newcomers. There are 12 lines and 150 stations served by up to 1400 buses, and most buses don't stop at all the stations on each line. There are maps in the stations that show which stations each bus stops at, but there's a real knack to working out which buses go where. One clue is in the bus number; bus B174, for example, will terminate at a stop on line B, but you'll have to look at the map to find out where it actually goes. The buses have little displays inside them that show the names of the next two stations, but there are no maps inside the buses, so once you're on board, it all starts to feel like a bit of a gamble. Luckily the Bogotans are lovely and will point you in the right direction, but when the digital display isn't working (which was the case for at least two of our journeys), it's all a bit random. The secret is to use the online planner in advance to work out exactly which buses you need; winging it is not for the faint-hearted.
Random is a good word for the stations, too. They're like long, thin bus stops with glass walls on either side that separate you from the buses that whizz past, and you simply look for your bus number above one of the glass doors and wait there for the bus to arrive. In theory the doors slide open when the bus pulls up, but sometimes the doors fail to open (so locals have become adept at wrenching them open themselves), and sometimes the doors open to reveal nothing but an empty and treacherous highway. There are digital displays in the stations that show which buses are arriving and when, and more than once the doors slid open at the allotted time, even though there was no bus there, and the displays updated as if the bus had been and gone. There are clearly ghosts in the Transmilenio machine.
But despite the slightly overcomplicated feeling of the Transmilenio, there's no doubt that when it works, it works really well. And as an added bonus, you get to see the Bogotans up close, from businessmen and students all the way to in-bus buskers and people coming on board to sell you incense sticks. It's a real cultural melting pot, and because it's above ground, you get to look at the streets of Bogotá from the comfort of your bus seat (or, more often than not, from your standing-room-only spot in the aisle). We certainly wouldn't have been able to explore Bogotá so easily without it.