 The boulders were transported over 150 kilometres ( 93 mi ) from the source of the stone . The exact method of transportation of such large masses of rock are unknown , especially since the Olmecs lacked beasts of burden and functional wheels , and they were likely to have used water transport whenever possible . Coastal currents of the Gulf of Mexico and in river estuaries might have made the waterborne transport of monuments weighing 20 tons or more impractical . Two badly damaged Olmec sculptures depict rectangular stone blocks bound with ropes . A largely destroyed human figure rides upon each block , with their legs hanging over the side . These sculptures may well depict Olmec rulers overseeing the transport of the stone that would be fashioned into their monuments . When transport over land was necessary , the Olmecs are likely to have used causeways , ramps and roads to facilitate moving the heads . The regional terrain offers significant obstacles such as swamps and floodplains ; avoiding these would have necessitated crossing undulating hill country . The construction of temporary causeways using the suitable and plentiful floodplain soils would have allowed a direct route across the floodplains to the San Lorenzo Plateau . Earth structures such as mounds , platforms and causeways upon the plateau demonstrate that the Olmec possessed the necessary knowledge and could commit the resources to build large @-@ scale earthworks . 
 The boulders <a href='uninflect' title='1'><mark>were</mark></a> transported over 150 kilometres ( 93 mi ) from the source of the stone . The exact method of transportation of such large masses of rock <a href='drop_aux' title='2'><mark>are</mark></a>unknown , especially since the Olmecs lacked beasts of burden and functional wheels , and they <a href='uninflect' title='3'><mark>were</mark></a> likely to <a href='been_done' title='4'><mark>have</mark></a> used water transport whenever possible . Coastal currents of the Gulf of Mexico and in river estuaries might <a href='been_done' title='5'><mark>have</mark></a> made the waterborne transport of monuments weighing 20 tons or more impractical . Two badly damaged Olmec sculptures depict rectangular stone blocks bound with ropes . A largely destroyed human figure <a href='uninflect' title='6'><mark>rides</mark></a> upon each block , with their legs hanging over the side . These sculptures may well depict Olmec rulers overseeing the transport of the stone <a href='null_relcl' title='7'><mark>that</mark></a>would be fashioned into their monuments . When transport over land was necessary , the Olmecs <a href='drop_aux' title='8'><mark>are</mark></a>likely to <a href='been_done' title='9'><mark>have</mark></a> used causeways , ramps and roads to facilitate moving the heads . The regional terrain <a href='uninflect' title='10'><mark>offers</mark></a> significant obstacles such as swamps and floodplains ; avoiding these would <a href='been_done' title='11'><mark>have</mark></a> necessitated crossing undulating hill country . The construction of temporary causeways using the suitable and plentiful floodplain soils would <a href='been_done' title='12'><mark>have</mark></a> allowed a direct route across the floodplains to the San Lorenzo Plateau . Earth structures such as mounds , platforms and causeways upon the plateau demonstrate that the Olmec possessed the necessary knowledge and could commit the resources to build large @-@ scale earthworks . 
The boulders was transported ova 150 kilometres ( 93 mi ) from da source of the stone . Tdaexact method of transportation of such bigass masses of rock unknown , especially since the Olmecs lacked beasts of burden and functional wheels , and they was likely to done used water transport whenever possible . Coastal currents of thdaulf of Mexico and in river estuaries might done made thedaterborne transport of monuments weighing 20 tons or more impractical . Two badly damaged Olmec sculptures depict rectangular stone blocks bound wit ropes . A largely destroyed human figure ride upon each block , with their legs hangin over the side . dese sculptures may well depict Olmec rulers overseeing the transport of the stone would b fashioned into their monuments . When transport over land was necessary , the daecs likely to done used causeways , ramps and roads to facilitate movin the hdas . The redanal terrain offer significant obstacles such as swamps and floodplains ; avoiding tdemwould done necessitated crossing undulating hill country . The construction of temporary causeways usin the suidale and plentiful floodplain soils would done allowed a direct route across the floodaains to the San Lorenzo Plateau . Earth structures such as mounds , platforms and causeways upon the plateau demonstrate that the Olmecdassessed the necessary knowledge and could commit the resources to buildbigasse @-@ scale earthworks .