Discuss the distinctive features of the Nagara style of Indian architecture and also state the important varieties of this style and their chief features.

The Nagara style was prevalent in the region between the Himalayas and the Vindhyas.
A study of these temples of northern India reveals two distinct features-one in planning and the other in elevation.
In plan, the temple was always a square with a number of graduated projections in the middle of each side. These projections give it a cruciform shape with a number of re-entrant angles on each side.
In elevation it exhibits a tower (Sikhara), gradually inclining inwards in a convex curve. The projections in the plan are also carried upwards to the top of the Sikhara, and thus there is strong emphasis on vertical lines in elevation. On account of this and the prominence of the vigorous and unbroken outline of the tower it is also known as the Rekha Sikhara.
The Nagara style is widely distributed over a greater part of India. It, therefore, exhibits distinct varieties and, ramifications in different localities, conditioned by the different lines of evolution and elaboration that each locality chose for itself. The cruciform plan and the curvilinear tower are, however, common to every medieval temple of northern India, wherever it is situated and whatever its local stamp might be.
On account of regional differences in the Nagara style of architecture, S. K. Saraswati has described the architecture of the temples of the Nagara style in six distinct regions- Orissa, Central India, Rajputana, Gujarat and Kathiawar, Deccan and Sindhu-Ganga valleys.