Actually, the OP was asking what is the minimum lenth for an enduro. Not the optimum lenth.

Which is why I said 90 minutes. 3 hours would be my favorite and the most often scheduled distance. Then I saw one "its not an enduro" after another.

The q was what is the minimum distance.

If we killed the under 6 hour enduros because, well, they aren't enduros. How many enduros would we have left?

As you say even the VIR 13 hours is struggling to survive.

I'd love to see a 5 or 8 race 3 hour enduro series. I think that would be a blast. But, i guess its not an enduro.

As for me...I am really looking forward to the ARRC 3 hour not an Enduro. I want that checkered flag for my trophy case. Enduro or not.