Considering the bands from 160 metres to 6 metres, which band offers the greatest ground-wave propagation distance?

Ground-wave attenuation (signal loss) is highly dependent on frequency. As the frequency of a radio wave increases, the Earth absorbs more of its energy, causing the ground wave to die out over shorter distances. Because lower frequencies suffer less absorption by the Earth's surface, they can travel much further along the ground. Out of the amateur bands listed from 160 metres to 6 metres, the 160-metre band has the lowest frequency (approximately 1.8 MHz). Consequently, the 160-metre band experiences the least ground-wave attenuation and offers the greatest ground-wave propagation distance compared to higher frequency bands like 40m, 10m, or 6m.