 In addition, water has caused cracking of the reinforced concrete core and rusting of its steel reinforcements and the fastenings of the monument, which also have been worn out by constant vibrations caused by traffic.The porous travertine has gradually crumbled over time and its pores have filled with soot and particles of sand, causing it to blacken and providing a habitat for small organisms, such as moss and lichens.Irregular maintenance and the unskillful performance of restoration work have also contributed to the weathering of the monument.