Why built airports near bodies of water?

Answer 1

Just in case the plane misses the runway they won't crash into a valley but instead crash into the water which is safer but the water has to be shallow or else they will drown.

And, primarily of course, many major cities are located near seas and rivers, so of course that is where their airports are.

Answer 2

One reason is safety. The body of water creates a perfect place for aircraft to ditch in. When something fails, the plane wouldn't crash into the populated cities to cause more damage.

Another reason is that the terrain won't be an issue above the water. Operations can be more freely and allow more airspace for the traffic, instead of a one-way-in and one-way-out situation.

And, primarily of course, many major cities are located near seas and rivers, so of course that is where their airports are.

Answer 3

They are not all built by shores.