▁narrow s ▁to ▁four ▁lan es ▁and ▁the ▁terrain ▁becomes ▁und ulating , ▁with ▁the ▁highway ▁rout ed ▁around ▁hills ▁and ▁through ▁valle ys ▁along ▁the ▁sh ores ▁of ▁Lake ▁Ontario . ▁At ▁Tr ent on , ▁the ▁highway ▁cross es ▁the ▁Tr ent ▁Canal ▁and ▁returns ▁to ▁an ▁agricult ural ▁setting . ▁It ▁then ▁cross es ▁the ▁Mo ira ▁River ▁as ▁it ▁goes ▁through ▁Belle ville ▁before ▁heading ▁east ward ▁to ▁King ston . ▁The ▁King ston ▁portion ▁of ▁the ▁highway , ▁originally ▁named ▁the ▁King ston - B yp ass , ▁was ▁one ▁of ▁the ▁first ▁sections ▁of ▁the ▁highway ▁to ▁be ▁completed ; ▁it ▁is ▁now ▁mostly ▁three ▁lan es ▁each ▁way . ▁ ▁East ▁of ▁King ston , ▁the ▁highway ▁continues ▁through ▁a ▁pre domin antly ▁agricult ural ▁area ▁alongside ▁the ▁Saint ▁Lawrence ▁River ▁to ▁Gan ano que , ▁where ▁it ▁spl its ▁with ▁the ▁Th ous and ▁Islands ▁Park way , ▁one ▁of ▁the ▁original ▁sections ▁of ▁the ▁highway ▁designated ▁in ▁ 1 9 5 2 . ▁The ▁current ▁Highway   4 0 1 ▁runs ▁parallel ▁to ▁the ▁park way ▁several ▁kilometres ▁in land ▁from ▁the ▁river . ▁The ▁Canadian ▁Sh ield , ▁an ▁ancient ▁ge ological ▁formation , ▁appears ▁through ▁this ▁heavily ▁for ested ▁section ▁of ▁the ▁highway . ▁Highway   4 0 1 ▁rejo ins ▁the ▁Th ous and ▁Islands ▁Park way ▁immediately ▁south west ▁of ▁Bro ck ville , ▁now ▁heading ▁n ortheast . ▁ ▁The ▁remainder ▁of ▁the ▁highway ▁runs ▁parallel ▁to ▁the ▁former