▁the ▁Metropolitan ▁City ▁of ▁Gen oa ▁in ▁the ▁Italian ▁region ▁Lig uria , ▁located ▁about ▁ ▁east ▁of ▁Gen oa . ▁ ▁Us cio ▁borders ▁the ▁following ▁municipal ities : ▁A veg no , ▁L umar zo , ▁Ne ir one , ▁S ori , ▁Trib og na . ▁ ▁References ▁ ▁Category : C ities ▁and ▁towns ▁in ▁Lig uria <0x0A> </s> ▁Most ▁rivers ▁in ▁Iran ▁are ▁season al ▁and ▁have ▁tradition ally ▁not ▁been ▁able ▁to ▁supply ▁the ▁needs ▁of ▁urban ▁settlement s . ▁Major ▁rivers ▁like ▁the ▁Ar v and , ▁Ar as , ▁Z ay ande h , ▁Se f id ▁and ▁At rak ▁were ▁few ▁and ▁far ▁between ▁in ▁the ▁vast ▁lands ▁of ▁Pers ian ▁anti qu ity . ▁ ▁With ▁the ▁growth ▁of ▁urban ▁settlement s ▁during ▁the ▁ages , ▁locally ▁d ug ▁deep ▁well s ▁( up ▁to ▁ 1 0 0 ▁meters ▁deep ) ▁could ▁no ▁longer ▁keep ▁up ▁with ▁the ▁demand , ▁leading ▁to ▁the ▁system atic ▁dig ging ▁of ▁a ▁special ized ▁network ▁of ▁can als ▁known ▁as ▁Q an at . ▁ ▁Q an at ▁and ▁Kar iz ▁ ▁Pers ia ' s ▁Q an at ▁system ▁dates ▁back ▁many ▁centuries , ▁and ▁thousands ▁of ▁years ▁old . ▁The ▁city ▁Z arch ▁in ▁central ▁Iran ▁has ▁the ▁oldest ▁and ▁longest ▁q an at ▁( over ▁ 3 0 0 0 ▁years ▁and ▁ 7 1   km ▁long ) ▁and ▁other ▁ 3 0 0 0 ▁years ▁old ▁q an ats ▁have