This is a formal combined driving event usually held over two days. Dressage and Cones competitions are held on the first day, and a "B" section only Marathon is held on the second day.
Section B includes all the Obstacles as well as the pathways (course) used to get from obstacle to obstacle between the Start and Finish markers. Course length is usually 1 km per obstacle.
Time is recorded for the Marathon, and includes time on the entire course as well as the time within each obstacle-which adds penalty points for obstacle elapsed time. There is a specified speed for each level/eqiune size which determines the time window for the marathon course. Additional penalties are added for being too early or too late based on that window.
Scores (penalties) for Dressage, Cones, and Marathon are combined to determine placing in the various classes.
Julie Mitchell at Shady Oaks
This is usually a one-day formal competition that combines a Driven Dressage Test and a Cones Course as the only Event sections. There is no Marathon or Obstacles section.
Not sure who this is. Believe the picture was taken at Grass Ridge.