It took us about 3 hours from Seminyak so maybe 3.5-4 hours depending on time of day and traffic.
I think between 2.5 and 3.5 hours - depending on traffic and stops. For a day trip, best would be to combine with other attractions - such as the Tegenungan Waterfall or Bias Tugel beach. Hope this helps.
PS Don't forget your swimsuit.
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