In many ways Herculaneum is arguably a more interesting place to visit than Pompeii. Surrounded by volcanic rock, its location gives you a far clearer idea of the magnitude of the volcanic eruption. While roofs in Pompeii collapsed under the weight of falling ash, only a few centimetres of ash fell on Herculaneum, causing little damage. Subsequently, there was a succession of six flows of boiling mud (a mixture of ash and gases) which then solidified. These gradually buried the city's buildings from the bottom up, causing relatively little damage. The good state of preservation of the site is due to its rapid filling by these flows, which prevented the buildings from collapsing. The high temperature of the first flow carbonized wood in the buildings and extracted water from it. Restoration work is ongoing, and while a lot of the timbers have been replaced, there is still much of the original timberwork present, albeit badly charred. Finally, the volcanic rock, or tufo , that covered the site for 1700 years formed an airtight seal. As a consequence there are many well-preserved buildings, many with the upper stories still intact, and some excellent frescoes and mosaics on both walls and floors to be seen. Herculaneum really gives you an idea of how ancient Romans lived. For the independent traveller there is an additional advantage over Pompeii. The congested streets around the excavations (it: scavi ) mean that access for tour buses is impossible. Thus there are far fewer visitors to Herculaneum than Pompeii. You don't have to fight your way past hordes of other tourists in order to get into the buildings and you can explore the ruins at leisure without being overwhelmed by tour groups. These excavations also cover a much smaller site than do those of Pompeii and thus seeing the whole site is much less exhausting.