What is the purpose of a movable bridge?

Related questions

1. Which truss bridge can hold the most weight?
2. Who built signature bridge?
3. What are the 4 major types of bridges?
4. What is special about Signature Bridge?
5. Why is a truss bridge the strongest bridge?
6. What is the strongest type of bridge?
7. What is the main purpose of bridge?
8. What is the longest cable stayed bridge in the world?
9. How do you make a bridge stronger?
10. Why do bridges have cables?

Tags

1. #stops
2. #boats
3. #cases
4. #moveable
5. #building
6. #passage
7. #allow
8. #shape
9. #lower
10. #change
11. #traffic
12. #because
13. #approaches
14. #piers
15. #river
16. #bridge
17. #below
18. #position