This stuff is for social studies
Idk d it might be d i might be wrong
Evolutionist say about 4billion years ago but if you want to know how long creation scientists believe than 6,000 to 7,000 years ago
Railroads changed ideas about travels because it gives easier access to deliver items to another destination or easier access to travel from one place to another in faster motion, rather than in the late 1800s individuals had to build their own transportations to trade or arrive at a certain place which took months and years