Reasons for Building a Bridge
The reasons for building a bridge include the need to:
- cross something (rivers, valleys, roads, railways) that is in the
way for safety reasons (such as a pedestrian bridge overtop of a major
road);
- cross something for performance reasons (such as Lethbridge's
railway bridge); and/or
- cross something for convenience reasons (such as the +15 walkways
that exist in Calgary, Alberta, Canada.).
See also human needs met by a bridge.