The basic requirements of an ideal alignment between two terminal stations are that it should be :

a) Short

b) Easy

c) Safe and

d) Economical

Short: It is desirable to have a short (or shortest) alignment between two terminal stations. A straight alignment would be shortest, though there may be several practical consideration which would cause deviations from the shortest path.

Easy: The alignment should be such that it is easy to construct and maintain the road with minimum problems. Also the alignment should be easy for the operation of vehicles with easy gradients and curves.

Safe: The alignment should be safe enough for construction and maintenance from the view point of stability of natural hill slopes, embankment and cut the slopes and foundation of embankments. Also it should be safe for the traffic operation with safe geometric features.

Economical: The road alignment could be considered economical only if the total life cycle cost considering the initial cost, maintenance cost and vehicle operation cost is lowest. All these factors should be given due consideration before working out the economics of each alignment.

The alignment should be such that it would offer maximum utility by serving maximum population and product.

Thus in summary it can listed as :

1.The length of the highway should be shortest and straight as possible.
2.The proposed alignment should form a most economical line of communication.
3.The alignment should be such that it is easy to construct and maintain the road with minimum problem.
4.The alignment should provide easy and safe driving conditions. Also safe from the view point of stability and natural hill slopes, embankment and cut slope etc.
5.The proposed alignment should be fit into the latest general planning of the country.