The non la hats are made of readily available materials such as palm leaves, tree bark and bamboo and are visible everywhere in the city, a UNESCO World Heritage site. Hoi An's history as a busy trading port is evident throughout its architecture, a mix of eras and styles, with traditional wooden Vietnamese houses, Chinese temples and French colonial buildings. REUTERS/Jorge Silva SEARCH "SILVA HATS" FOR THIS STORY. SEARCH "THE WIDER IMAGE" FOR ALL STORIES TPX IMAGES OF THE DAY