Fly into Warsaw and take train 1.5-1.75hrs to Łódź. Trains run very often and are fast, nice, comfy trains. Also can fly into Berlin and train 5 hours from there. A few other options especially if doing other trip(s) before wedding, but Warsaw definitely the most practical option, followed by Berlin or Krakow.

Once in Łódź, getting around via public transit (and probably mostly walking) is very easy — public transit actually exists in Europe! So it’s unlikely you’d find much use or need for a rental car. Text me (816-522-1200) or Marta (785-226-6505) or email (pmcnamara10@gmail.com, marta.kapszewicz@gmail.com) if you’re on the fence about rental car and have Q’s, or any other travel Q’s!