Alghero is the tourist capital of the so-called Coral Riviera. Its Spanish heritage is reflected in many buildings, including the church of San Francesco and the towers and bastions remaining from Spanish fortifications. With its 22 impressive columns, the Church is an outstanding example of Catalan-Gothic architecture. Grottoes and caves attract the adventurous visitor; fishing boats and pleasure craft crowd the colorful harbor; and the crystalline sea is ideal for coral and lobster fishing. Old Town is the site of seven defensive towers that dominate the walls surrounding Alghero. One of the most prominent is Porta Terra, known also as Jewish Tower. At Via Umberto stands Alghero