3 Summer Classes in one session?

How manageable/intense would it be to take 3 summer courses at once during the same session? My options are to either take these three classes all once in a seven week summer session, or to add an additional semester to my graduation timeline, and I'm leaning heavily towards the former, lol I really want to graduate by the end of the year. They are all humanities classes, my writing & time management skills are pretty solid, and I will not have a job over the summer so I feel like it will be doable...? Just curious if anyone has any experiences to share having done this, or if I'm just asking for a bad grade or dropped class with a ridiculously unmanageable workload.