Various means were probably used to transport and to erect the "large stones". Most modern attempts to do the same with blocks weighing up to several dozen tons, have been successful, proving that the feat does not require superhuman powers.
Various transportation methods have been suggested and tried out, including rollers, levers, manual haulage and floating. Sand and counterweights may also have been used to secure the blocks in position.
Although most blocks were not reworked, some were adjusted by cutting (as in Gavrinis) or by pecking (e.g. the Grand-Menhir at Locmariaquer).
Some of the large blocks at Locmariaquer were obviously cut, as shown by the small cupmark lines along the edges. However, it is not yet clear which technique was used.
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Floating the Grand Menhir downstream, using a raft and dug-out canoes

Megalithic block rolling experiment at Bougon  (Deux-Sèvres) in 1997.

It took 500 men to carry out the same experiment as above in 1979, using the classic tug-of-war technique.