Sadly some tourists Domestic as well as Foreign , see Goa's relatively liberal attitudes as an excuse to give no thought to the culture and customs of the local community. Goan's like the rest of India dress modestly, and Nudism which includes going topless , is illegal, but many foreigners do it . Sadly this has given Goa the reputation throughout India, as a place where " loose women bare all "
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The Goans living along the beach , who earn their living from tourism , don't say anything , but don't really like it , and many blame the incidents of assault and harassment of foreign women on this behaviour . In respect of the culture it's also best to cover up when visiting Towns, and at Religious sites no shorts or vest tops.
Sorry if this sounds like a lecture, but some newcomers might find it helpfull