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meet the requirements of indicator boulders. Both cases suggest that the boulderswere transported in the southeast and south–southeast directions. The only certainindicator rock among large boulders is the unique gneiss-breccia originating from theclearly identified impact structure in northwestern Estonia. From there, largeboulders have moved about a hundred kilometres to the south–southeast by azimuth155°, while smaller boulders form typical diffusive dispersion fans (Fig. 31).Economic activityErratic boulders have considerably influenced the local economic activity. Forcenturies people have tried to clear fields from boulders that hinder tillage usingprimitive methods and tools (Fig. 32). The registered data show that the volume ofboulders removed from the fields after World War II exceeds tens of times thevolume of the famous Cheops pyramid in Egypt (Fig. 33). However, mainlysmaller boulders have been relocated, while larger ones have mostly remained intheir initial location, since their removal would have needed considerable effort andspecial machinery. Similarly, mostly small and more easily workable boulders havebeen used in construction.Large boulders have been used as landmarks, especially as permanent seamarksin coastal areas, where a fire lit on top of a rock or at its foot served as a primitivebeacon. Large boulders have also been used as benchmarks and historic waterlevels have been carved into them. Boulders have often been chosen as boundarymarkers, historic events have occurred near them, the evidence of various eventshas been carved on their surface, etc. Even nowadays, in forested areas many largeboulders serve as important permanent landmarks.Legends, culture and nature protectionLarge erratic boulders have been inexhaustible sources for local folklore – sinceancient times innumerable legends and beliefs have been told about them. Later thesestories have been recorded in writing and thus they have reached today’s culture andremarkably influenced the national consciousness. Large boulders are generallyrespected, people do not destroy or litter them and even nowadays it is believed thattreasures may have been buried under them. Today’s nature protection arrangementsare based on this general respect (Fig. 34). Naturally, attention is paid mostly to thelargest erratic boulders. Therefore, about 75% of huge boulders (perimeters over25 m) are protected by the nature conservation regulations, while in the case of lessfrequently protected smaller boulders their specific shape, related folk stories andhistoric events are considered (Fig. 35). Managing nature conservation is a dynamicprocess, the measures, laws and regulations of which are constantly amended andimproved, due to the active involvement of local communities. As the public awarenesson nature conservation in Estonia has always been high, it creates favourableconditions for preserving the unique association of abundant large boulders also forfurther investigations.108