On the 2m band (144 to 148 MHz in the 'States, so called VHF), using pure line-of-sight (no obstructions), I can routinely talk 50 mi to 100 mi using ~10W and omni-directional antennas at both ends. Flying at ~10,000 ft, I talk hundreds of mi, limited only by earth curvature.
A VHF signal will reradiate off a mountain ridge, so it is possible to communicate into the neighboring valley where no line-of-sight exists using "knife-edge" scattering. Did that today.
I can also fire up on 160m, 80m, 60m or 40m, the short-wave bands, (depending on time of day), and bounce a signal off the ionosphere to communicate from a few tens of miles out to about 1500 miles. Did that today.