Zugliget places you directly at the edge of the Budai Hills, and Night Trail Budapest is precisely that: night trail running in the hills with a headlamp. The Hungarian description calls it a “unique experience,” and that seems accurate; this is not a road race starting in the dark, but a trail run organized around running after daylight has ended.
The surface is trail, the total elevation gain is listed as 700 m, and the headlamp is required equipment. With the field limited to 500 participants, anticipate a focused group of runners who are there for the quiet, technical rhythm of moving through the Budai Hills after dark, not for roadside cheering or large-scale events.