Depends on what the question refers to:
The longest "running" event is the Marathon, but the longest event in terms of distance in the athletics is the Mens 50 kilometre walk (but you certainly aren't allowed to run in that).
Alternatively there are a whole series of events that have been included in every Olympics, therefore there is no single longest running event in terms of being at every Olympics.
Depends on what the question refers to: The longest "running" event is the Marathon, but the longest event in terms of distance in the athletics is the Mens 50 kilometre walk (but you certainly aren't allowed to run in that). Alternatively there are a whole series of events that have been included in every Olympics, therefore there is no single longest running event in terms of being at every Olympics.
1500m
What is the longest soul music event
Yes. The Marathon is second at 42.195 km and the 20 km walk is third.
It's the longest Someone
The answer is running
Yes
There was only on running event played in the Ancient Olympics, the short sprint from one side of the stadium to the other.
The longest runing sporting event in the USA is the Kentucky Derby
The longest event for speed skating is the men's 10,000 meters race, which is equivalent to 10 kilometers.
The Marathon.
Foot races