The Nepal Army runs the main programme at Tundikhel, and it is a full afternoon rather than an interval between races.
The sequence typically takes in mounted charges across the field, trick and acrobatic riding, gymnastic and combat demonstrations, motorcycle stunts, and a formal parade reviewed by the President — a review the King performed before 2008, which is one of the clearest small examples anywhere of a royal ritual simply being handed to a republic without a break.
It is a genuine spectacle and the stands fill early. It is also a useful thing to see for what it says about the day: the horse racing is a Newar observance about a demon, and the state has wrapped a national military display around it without either half displacing the other. Both are happening on the same field at the same time and nobody finds this contradictory.
The day is a public holiday, and the ground fills with families picnicking and food vendors well outside the roped display area.
Related Places & Sites

Deities & Presences
Characters
Rituals & Ceremonies
Part of Ghode Jatra