To combine the unity of a central plan with the direction a church needs, plan the space as an oval, set across the axis to widen the view of the altar, or along it to lead the eye towards it.
Radial streets from a central square
Run the principal streets straight from the central square to the gates, so that every gate is visible from the centre and every quarter lies on a direct route to it; set secondary squares along the radials.
The radial plan expresses a political idea (every part of the city looks to the prince at its centre) and a military one: troops can move quickly from the centre to any gate. At Palmanova (1593) six main streets leave the hexagonal central piazza; three lead to the gates, and further streets begin at the first ring road. Baroque Rome and Versailles transferred the idea to the scale of the landscape, with avenues radiating from a square or a palace.
Related rules
Let the wall of a façade curve in plan (concave, convex, concave) so that the front answers the street, the light and the space within, and the order bends with it.
Make the stair of a palace a processional space: one broad flight rising to a landing, then turning back in two flights either side to arrive at the principal floor beneath a single great vault.
Give the villa garden porticoes for sun and for shade, grottoes made in imitation of nature with tufa and shells, evergreens planted in straight rows at equal distances, and hedges of box; set vines on columns over the walks.
Lay the ideal garden out on a circular plan in concentric rings, woods outside, then meadows and orchards, then gardens of knots and clipped evergreens divided by walks, with water and the fountain of the goddess at the centre.
Make the parterre oblong rather than square, since figures somewhat oblong look better on the ground than square ones; later practice made it as broad as the front of the house and about twice as long.
parterre oblong; later practice: width ≈ house front, length ≈ 2 × width
Cite this page Chris Paton, “Radial streets from a central square”, The Textbook of Architecture, https://textbookofarchitecture.com/rule/radial-streets. Text, drawings and models licensed under CC BY-NC 4.0.