Zipline y aerial bikes

Heights make me feel a little insecure and nervous... Not when I get on a plane or ride a fairground attraction where I'm seated, but when I'm on the edge of a roof or a cliff or something like that. I don't know if it has to do with age, since as a child I never felt any fear, but now that I'm an adult I feel a loss of balance and don't risk going on rides like this. Maybe with the ropes and everything else I wouldn't feel anything, I'll have to try it sometime. These images are from Finca Rauda in El Salvador.