Just because the peak portrayed here is geometrically not visible from the observation point (the highest peak in Poland). That small Romanian peak is appearing due to refraction, that curves the light beams across the atmosphere and allows hidden objects to show as if they were visible.
A great example of how refraction is something to very care about in distant observations.
After days of researching, Marc discovered that certain peaks in Maritime Alps range will show in front of the sun at sunrise near summer solstice, in concret 13th July for the first of them. Even better, this event will became in a new world record for distant sighting.
Three and a half weeks before and after the winter solstice, the sun rises behind Sierra de Tramuntana in Mallorca island, as seen from a summit in southern Catalonia. This is helpful to portray those mountains, which would otherwise require higher transparency.