St. Peter's Square site features

You come down a straight avenue and the space opens sideways. Via della Conciliazione runs at the basilica for half a kilometre, and then the buildings stop and the square spreads out on both sides at once — an oval, not a rectangle, held by two enormous curved arms of columns that reach toward you like a pair of brackets.

The colonnade is four rows deep and open all the way through. You can walk inside it: a shaded corridor of pale travertine columns, with daylight cutting between them, running the whole curve. On the cornice above, a row of saints in stone, well over life size, stand along the top looking down into the square.

In the middle, an Egyptian obelisk. Red granite, unmarked by hieroglyphs, over 25 metres of single stone and nearly 40 with its base and cross. Around its foot the paving is laid as a compass rose; on either side, a few metres out, are two round stones set flush into the pavement.

Those two stones are the point. Stand on one and the four rows of columns slide into alignment: the colonnade appears to be a single file of columns, one row deep, all the way round. Step off and it thickens again.

Two fountains throw water on either side, matched but not identical, and the ground tilts very gently up toward the basilica at the far end — so the facade, Maderno's 115 metres of it, closes the view with Michelangelo's dome rising behind and mostly hidden by it.

The two roundels

Round stones set in the paving either side of the obelisk, six or seven metres beyond the outer ring of the compass rose. From either, the four rows of the colonnade become a single file of columns.

The colonnade

Turismo Roma: 284 columns radially in four rows, eleven years of work, 1656-1667. The reference work: 248 columns and 88 pilasters, with 140 over-lifesize saints crowning the cornice, 1667-1676.

The obelisk

Red granite, over 25 metres, nearly 40 with base and cross. Erected at Heliopolis by an unknown pharaoh; moved here in 1586 by Domenico Fontana.

The two fountains

A granite fountain built by Bernini in 1675 matching one designed by Carlo Maderno in 1613.

The Angelus

Turismo Roma records that every Sunday at noon a large crowd gathers for the Angelus Domini and the Pope's blessing.