What were the physical obstacles railroad construction faced?

Railroad construction faced several physical obstacles, including varied terrain such as mountains, rivers, and swamps. Engineers had to navigate steep grades and rocky landscapes, often employing tunnels, bridges, and cuttings to create feasible paths. Additionally, weather conditions and the need for stable foundations in soft or unstable ground posed significant challenges, requiring innovative engineering solutions. The presence of natural barriers also necessitated careful planning and resource allocation to ensure safe and efficient routes.