You will see offering plates similar to these all over the island of Bali in Indonesia. These offering plates are a central part of Balinese Hinduism and and placed in front of every house and business every day. These offering plates were sitting on the beach.
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Too many people travel to Bali without knowing anything about the culture. It is good you write these little tidbits so at the very least people aren't surprised by it.
That called Banten. Hope you enjoy Bali, Gary…
what is that? are u call it “sesajen?” :)