We study the effect of railway access on regional development in 19th century Switzerland. The identification strategy in our analysis of geo-referenced railway network information, population growth rates, sectoral work shares and body height, relies on panel data techniques and an inconsequential units IV approach. Gaining railway access increased annual population growth by 0.4 percentage points compared to unconnected municipalities, mainly via the local migration balance. Railway improvements also promoted structural shifts from the primary to the secondary/tertiary sectors, and marginally accelerated body height growth