Biomass burning from wildfires, prescribed burns, agricultural fires, and domestic heating emits large amounts of carbonaceous matter, having adverse effects on air quality, human health, and climate change (Chen et al., 2017). In the Czech Republic and neighboring states (i.e., Germany), the traditional Burning of the Witches (BoW) is celebrated during the night from 30th April to 1st May by lighting bonfires made of biomass material (woodpile, dry grass, etc.). According to the Czech Fire Department, around 8,000 fire spots were reported in 2023 (Czech Fire Rescue Service, 2024), making this event the largest non-heating open-air biomass burning experiment in Central Europe. In this study, the vertical distribution of carbonaceous aerosol was investigated during the BoW, combining measurements at the foot and on the top of a 250 m tall tower.