By Doug Criner

Streets and walkways in Pompeii are mainly paved with quarried basalt, a hard, black material formed by solidified lava.  (Today, because of its hardness and resistance to erosion or wear, basalt is sometimes used to line the inside of pipes carrying abrasive powders or slurries.)

It might seem ironic that basalt was readily available from prior eruptions of Vesuvius, yet the doomed residents seemingly had no inkling that Vesuvius was a dangerous volcano waiting to destroy their city.  However, these same environs, now in the 21st Century, are once again densely populated with residents who seem oblivious of any danger, but perhaps are better prepared to run for their lives in the event of an eruption.

Photo 1 - Typical Basalt-Paved Street in Pompeii

Photo 1 depicts a basalt-paved street, along with basalt curbs.  Like modern streets, the middle is crowned for drainage, and there are shallow gutters at either edge of the roadway.  In addition to stormwater, it is likely that wastewater flowed down the streets.

Basalt is very smooth and hard, and is treacherous to walk upon when it is wet and slippery.  At the far end of the street of Photo 1 are four large stones aligned across the street.  These were evidently stepping stones for pedestrians to use in crossing the street.  The above-ground clearance of wheeled carts or wagons must have been sufficient for vehicles to straddle the stepping stones.

Photo 2 - Basalt-Paved Street

Photo 3 - Street Intersection With Stepping Stones

Photos 2 and 3 show additional street scenes.  The street in Photo 2 is relatively narrow.  Since it is at the rear of the adjacent buildings, it probably served as an alley.  (The downspouts on the buildings are modern.)

Photo 3 shows an intersection with the typical stepping stones for pedestrians.  The stepping stones and the street curbs are typically about 12-18 inches high.  When Photo 3 was taken, it was misting; the basalt pavers glisten with wetness and were quite slick.

Photo 4 - Wheel Ruts

Photo 5 -Wheel Ruts

Photos 4 and 5 shows wheel ruts eroded into the basalt pavement.  These ruts in such hard stone is evidence of iron-rimmed wheels with uniform gauge (distance between wheels on the same axle).  These streets clearly did not carry two-way traffic.  The street pavement shows no sign of settlement, indicating that a well-constructed and compacted sub-base was built beneath the roadway.

Photo 6 - Hole in Curbing

Photo 5 shows a curious hole bored in a basalt curb.  The purpose is unknown, at least to me.  Possible it was used to tether an animal.  Another possibility is that the hole was used to mount a pole for perhaps a flag or banner.

Photo 7 - Basalt-Paved Street in Modern-Day Sorrento

Use of quarried basalt for street pavement is still common in certain sections of modern-day Sorrento as shown in Photo 7.  However, modern basalt pavers are quarried in a more regular pattern than the cobbled appearance seen at Pompeii.  Also, the surface is not as smooth, providing better traction.

© Doug Criner, 2003