Okay, thank you. Are there any longer periods of time ?

There are longer ones, I remember 24-hour ones. It seems like there are also 48-hour ones. But I think the scenic spots in the city center are more concentrated, basically relying on walking. The 90-minute one I bought is mainly used for getting from the airport to the city center and from the old town to the castle district. So I feel that the long ones are not very cost-effective. Another thing is that the automatic ticket vending machines do not accept banknotes. So it's important to have some change. Of course, there are ticket counters at some larger transfer stations.