Italianjon, if you are flying VFR, then the semi-circular rule is only a recommendation, and the safe altitude marked on the chart (grid MORA; MSA is minimum sector altitude, a totally different animal) will only apply if you are not in sight of the surface, otherwise you can route around the highest points.
Sorry, in Germany when flying VFR above 5000ft amsl or 2000ft above ground it is MANDATORY to maintain a Flight Level according to the semicircular rules (55,75,95,115 from 0 - 179 degrees magnetic track, 65,85,105 etc from 180 degrees to 359 degrees).
Please note that this is NOT valid when climbing or descending or if following such rules would put you in contradiction with maintaining VMC conditions.
These rules are listed under the German LuftVO Anlage 3, Paragraph 31.2 for VFR, 37.3 for IFR......