Our fourth and fifth nights were spent in the beautiful town of Florence. Our road trip between Rome and Florence included a diversion through Umbria and Tuscany to a spot of great import to the geologists in our crew, the medieval town of Gubbio, and a unique outcrop of rock that is located nearby. Besides touring the downtown area of Florence, we spent an afternoon visiting Pisa, which they said was famous for some kind of bad architectural planning or something...click on the thumbnails below for a full-sized picture!

Gubbio and the Iridium Anomaly   File name Description Umbria Countryside We drove north from Rome into the hill country of Umbria. Beautiful towns could be glimpsed in the distance as we drove into the heart of the central Apennines. This photo may be in the vicinity of Orvieto and Todi. Driving to Gubbio The villages and towns in the region occupy the high ground...after the fall of the Roman Empire, the region descended into chaos, and walled towns in strategic positions became the norm. Entering Gubbio Gubbio is a typical medieval walled city (if there is such a thing), which occupies the base of a triangular facet, an eroded fault scarp. The region is crisscrossed by a series of fault lines, including earlier thrust faults, and more recent normal faults. The Gubbio graben is part of an active fault system. A magnitude 6 earthquake struck the region in 1997, causing serious damage, especially at Assisi. Gubbio The town is generally a quiet place today, except during some of their unusual festivals, including one that involves a race carrying huge 440 lb "candles" to the basilica of St. 'Ubaldo near the top of the mountain peak behind the town. Roman Theatre In more secure times, the inhabitants lived on the valley floor. The ruins of the Roman theatre lie in an open field, while the medieval walls surround the town in the distance. Bottacione Gorge Our main objective of the day actually lay a bit east of the town in the Bottacione Gorge. In the 1970's, Walter and Luis Alvarez discovered an intriguing chemical anomaly in the limestone layers of the gorge, at the boundary between rocks of Cretaceous age (the dinosaur era), and the Tertiary (the age of mammals). Limestone outcrops in the Bottacione Gorge Iridium most often comes from asteroids and meteorites impacting the earth, and is otherwise very rare. The average abundance of the element in ocean sediments is 12-13 ppt (parts per trillion). At the K/T (Cretaceous/Tertiary) boundary, the abundance jumps to 3,000 ppt. Following the data, the Alvarez team suggested a new hypothesis explaining the extinction of the dinosaurs and other animal groups...a giant asteroid impact. Walking to the outcrop After a false start that required a very tricky bus turnaround, we found the site, and set out to see a piece of geologic history... The K/T Boundary And there it was! A place where we can lay our hands on the moment when the world changed forever... Group studies the outcrop If you need to find the outcrop on your own journey, it is about a mile east of Gubbio. If you pass the Medieval water-works, you've gone too far. A sign marks the site. Medieval waterworks The site is interesting, sits in a beautiful gorge, but we had one more pleasant surprise...it was late, we had not eaten lunch, and there seemed to be no good prospects for lunch, except maybe that little tavern down the road.... The tavern! The owner was delighted at the possibility of feeding a busload of 40 hungry American tourists. And not only that, he has been feeding a full generation of geologists who have visited the site...it was our best lunch of the entire expedition! The register And we got to sign the register of the all the geologists who have stopped in!

Florence and Pisa   File name Description Tuscany countryside The remainder of the day was spent on countryside roads and the autostrada to Florence, one of the most beautiful cities in Italy. Over and over I was struck by the ancient nature of the culture and landscape; this is a land dominated and used by humans for thousands of years. I used to think of California's missions as ancient buildings because they dated back to the late 1700's. Cities in California are ancient if they were established before 1900. We passed towers and barns and homes that were not notable in any way to the locals, yet they had been standing for many centuries. Tuscany countryside In Europe, buildings from the 1700's and 1800's represent recent urban renewal! This house was notable for being so young, but I liked the juxtaposition of ancient and modern in so many places that we traveled. Museo Mediceo And of course there was an official appreciation of art that is sometimes missing in more familiar places back home. We arrived in Florence late in the afternoon, and wandered about the center of the city. We had walked no more than a few blocks before we passed the courtyard of the Medici family, and could see the statues in the foyer... San Lorenzo Church We walked past the Basilica of San Lorenzo in the sunset. The church was constructed in the 1400's, one of the younger churches in the city center. Cathedral of Santa Maria del Fiore After dinner in a downtown restaurant, we wandered into the Piazza San Giovanni for a look at the Cathedral of Santa Maria del Fiore, known more often simply as "Il Duomo". The church was begun in 1296, and the dome was designed and constructed under the direction of Brunelleschi from 1420-1436. The bold lines around the windows reveal a new facet of local geology...marble! The coastal mountains, the Apuan Alps, contain exposures of several different kinds of marble in a multitude of colors, including the famous white Carrara Marble favored by Michelangelo. Cathedral of Santa Maria del Fiore The facade of the church, seen here the next morning, is a striking contrast to other churches we had seen...the green was serpentine marble, the pink was marble containing iron, and the pure white marble of the Carrara region along the nearby coast. Giambologna sculpture Marble, of course, is a wonderful medium for sculpture, and beautiful marble statues can be seen throughout the city. A marvelous open-air museum at the Loggia della Signoria includes a piece carved from a single piece of marble by Giambolgna in 1583, the Rape of the Sabines. Michelangelo's David For centuries, Michelangelo's 17-foot tall sculpture, David, stood in the Piazza Della Signoria. Damaged by weathering, it was moved to the Accademia in the 19th century, and this replica put in its place. I think of myself as a patient person, but in this instance, a two-hour wait in line at the Accademia was too much, so we settle for the copy... Vegetable Stand No geology here, just food art! Alley As a geologist who enjoys wide-ranging views of a landscape, I came to very quickly appreciate the architects of the city center, who left beautiful open squares near the churches and cathedrals...all the alleys and streets are claustrophobically narrow! Flower Girl This is here simply because the little lady was enjoying the wedding and being cute Palazzo Vecchio The tower was constructed from 1299-1302, and at 308 feet, was an engineering triumph for the time. The Ponte Vecchio The Arno River flows through the center of Florence. During the retreat of the Nazis from here in 1944, all of the bridges spanning the river were destroyed, except for one, the Ponte Vecchio, which was originally built in 1220. The buildings have housed jewelry and gold shops for centuries. An unprecedented flood in 1966 nearly swept the bridge away, and also destroyed and damaged a heart-breaking number of classic artworks in the churches and museums lining the river. The river reached a depth of 22 feet, and was flowing at a rate of 70,000 cubic feet per second.   Damaged art It was said that during the flood of 1966, countless invaluable works of art were simply floating away in the muddy river. 14,000 movable art pieces, and 3 to 4 million priceless books and manuscripts were damaged and destroyed. Some artworks that were recovered had lost all the paint, and retained only the pencil marks made by the artists. The badly damaged wooden Crucifix by Giovanni Cimabue is on display in the Basilica of Santa Croce. The church also houses the tombs of Galileo, Michelangelo, and Machiavelli.   Campo dei Miracoli I guess all trips to Italy have to include a look at the Leaning Tower of Pisa. So it was that we took the 90 minute journey to the small town. Unlike most of the churches we had seen, the bell tower (campanile), the baptistery, and the duomo stand apart from the rest of the town in an attractive green field called the Campo dei Miracoli (field of miracles). At least the tourists and their promoters call it that. The town is Pisa is just down the coast from the Carrara marble quarries, and attractive stone is nicely used on the church buildings here...   The Leaning Tower The Leaning Tower was begun in 1174, and started listing almost immediately. Construction ceased at the third floor for a century as the engineers tried to figure out how to stop the tilting. The problem is that the town of Pisa is built upon saturated, clay rich soils that are a poor foundation for buildings of any kind. All of the buildings in the complex tilt to some degree. The total tilt today is 14 feet, and apparently has been stabilized after a full scale effort in 2001. Leaning Tower Repaired! Fixing the tilt was easier than anyone expected. Here is the Leaning Tower without the lean!!!