the Oreti Railway in New Zealand which opened in 1864 used wooden rails

This isn't to say that they didn't put iron strips on the top of the wood rails. the first Locomotive in Canada ran in wooden rails with iron strips fixed to the top https://www.facebook.com/photo.php?fbid=3096220380566742&set=p.3096220380566742&type=3 https://www.facebook.com/photo?fbid=1965516564327069&set=gm.26883259127998760&idorvanity=1614960195255335