Why did the Pony Express end?

Related questions

1. What route did the Pony Express take?
2. Who was Buffalo Bill Serial Killer?
3. What is a Pony Express station?
4. Did William Cody ride for the Pony Express?
5. Where did the Pony Express route begin and end?
6. What was the average age of a Pony Express rider?
7. Who was the oldest pony express rider?
8. How long did it take the pony express to go from coast to coast?
9. Was Wild Bill Hickok real?
10. Did Buffalo Bill wear wigs?

Tags

1. #opening
2. #riders
3. #close
4. #faster
5. #telegraphs
6. #business
7. #height
8. #october
9. #opened
10. #horses
11. #expense
12. #april
13. #could
14. #closed
15. #telegraph
16. #after
17. #forced
18. #express
19. #transcontinental
20. #around