▁were ▁wide ▁by ▁medieval ▁standards , ▁ 2 0 ▁metres ▁across , ▁with ▁wide ▁gra zing ▁ver ges ▁on ▁either ▁side , ▁the ▁" long ▁a cre ". ▁ ▁In ▁medieval ▁Spain ▁the ▁existence ▁of ▁mig rat ory ▁f lock s ▁on ▁the ▁largest ▁scale , ▁which ▁were ▁carefully ▁organ ised ▁through ▁the ▁system ▁of ▁the ▁M esta ▁gave ▁rise ▁to ▁order ly ▁dro vers ' ▁roads , ▁called ▁cab añ eras ▁in ▁Arag on , ▁car rer adas ▁in ▁Catal onia , ▁az adores ▁real es , ▁emphas ising ▁royal ▁patron age , ▁in ▁Val encia , ▁and ▁most ▁famous ▁of ▁all , ▁c añ adas , ▁including ▁three ▁major ▁c añ adas ▁real es , ▁in ▁Cast ile . ▁Al ong ▁these ▁gra zing ▁track ways ▁sheep ▁travel led ▁for ▁distances ▁of ▁ 3 5 0 ▁to ▁ 4 5 0 ▁miles , ▁to ▁the ▁summer ▁past ur ages ▁of ▁the ▁north , ▁around ▁León , ▁S oria , ▁C uen ca ▁and ▁Seg ov ia , ▁from ▁the ▁middle ▁of ▁April , ▁and ▁returning ▁to ▁winter ▁past ur age ▁in ▁La ▁Man cha , ▁ ▁Est rem ad ura , ▁Alc ánt ara ▁and ▁the ▁low lands ▁of ▁And alus ia . ▁ ▁In ▁L angu ed oc ▁the ▁trans hum ance ▁path ways , ▁more ▁restricted ▁by ▁agricult ure ▁and ▁orch ards ▁and ▁less ▁organized ▁than ▁those ▁of ▁I ber ia , ▁were ▁the ▁dra illes ▁that ▁fed ▁into ▁the ▁main ▁car ra ï res , ▁which ▁led ▁from