All service buses in Spain, at least every one I've ever been on, have a flat rate fare. That makes it dead easy to ride buses without bumping into over helpful drivers, the sort who are determined to send you by the most effective, rather than the most scenic, route. In Spain, when people try to be helpful it can so easily fall apart because despite understanding what is said to me 95% of the time and having sufficient Spanish to make a cogent response 99% of the time that's not how it plays. It goes more like blubber, blubber, stammer, stutter, feel like a fathead.
Here, to get on a bus, you just pay your 95 centimos and take your ticket. In fact if I got around to buying one of the multiuse cards I could ride around for 50c a time. This means that Maggie and I have been on several buses just to see where they go. Cartagena is not a big place so, if a bus starts to take you into some mysterious district you can either stick it out to the terminus and then come back again or get off and walk the few metres to familiar ground.
I rode one of the two minibus routes from a stop pretty close to home this morning just to see where it went. Down to the back of the port and the shopping streets, the bit that hasn't been done up yet, the bit with the Moroccan barbers and Hal Hal butchers was the answer. I'd had a coffee in a bar and bought one for the tramp who tapped me up. I'd been in the big domed Church - La Caridad - where I was tapped again. As I came out I saw the other minibus, the route I've never been on, parked up so I got on. Fearless you know; the stuff that had Livingstone wandering around Africa. From a quick scan of the route it looked like I could get off near the Plaza de España and catch another bus home. The minibus routes don't go by direct routes, they tend to twist and turn using streets that proper single deckers would find tricky. In fact at the first junction we got to the road ahead was closed whilst a cement lorry unloaded. The driver did a bit of Bernie the Bolt "left a bit, right a bit" to get us back on the proper route. He and the other five passengers on board set up a jolly banter about taking the tourist route. I don't think any of them knew how right they were as the tourist watched the University buildings, the castle and the old bullring go by. I didn't need to change buses, the route went within 300 metres of home.