▁Sal is bury ▁ ▁This ▁segment ▁of ▁Route ▁ 1 A ▁extends ▁from ▁Boston , ▁Massachusetts ▁to ▁Sal is bury , ▁Massachusetts . ▁ ▁The ▁highway ▁starts ▁from ▁US ▁ 1 ▁( which ▁is ▁on ▁the ▁Central ▁Ar tery ▁with ▁I - 9 3 ▁and ▁Route ▁ 3 ) ▁at ▁the ▁former ▁Government ▁Center / Log an ▁Airport ▁inter change . ▁It ▁passes ▁through ▁the ▁Cal la han ▁T unnel ▁( out bound / n orth bound ) ▁and ▁Sum ner ▁T unnel ▁( in bound / s outh bound ), ▁becoming ▁the ▁East ▁Boston ▁Express way ▁past ▁Log an ▁Airport . ▁ ▁The ▁East ▁Boston ▁Express way ▁was ▁the ▁first ▁fre ew ay ▁built ▁in ▁the ▁city . ▁Im medi ately ▁beyond ▁Log an ▁Airport , ▁Inter state ▁ 9 0 ▁ends ▁at ▁Route ▁ 1 A . ▁ ▁The ▁road ▁continues ▁as ▁a ▁divided ▁highway ▁through ▁Re vere . ▁ ▁It ▁is ▁a ▁limited ▁access ▁highway ▁through ▁Re vere , ▁passing ▁Su ff olk ▁Down s ▁and ▁the ▁Wonder land ▁Grey h ound ▁Park ▁( which ▁is ▁across ▁the ▁street ▁from ▁the ▁outer ▁termin us ▁of ▁the ▁MB TA ' s ▁Blue ▁Line ), ▁before ▁running ▁through ▁the ▁isolated ▁Point ▁of ▁P ines ▁neighborhood ▁and ▁exit ing ▁Re vere ▁over ▁the ▁General ▁Edwards ▁Bridge ▁into ▁Lyn n . ▁ ▁For ▁the ▁first ▁mile ▁and ▁a ▁half ▁in ▁Lyn n , ▁it ▁is ▁concurrent ▁with ▁the ▁Lyn n way , ▁and ▁is ▁a ▁high - tra ffic ▁ret ail ▁area . ▁After