Quick answer: Mushroom Bay is the calmest and best for swimming, followed by Tamarind Bay and Jungutbatu at high tide. Sandy Bay, Dream Beach and Secret Beach have strong waves and are for calm days only.
The sea around Lembongan is powerful. The beaches facing the channel are sheltered and calm; the ones facing the open ocean on the south-west coast take the swell head on. And the tide changes everything: some beaches turn to reef flats at low tide. Here they are, ranked from calmest to strongest.
Mushroom Bay
The calmest swimming on the island: a sheltered bay with soft sand on the west coast. Good for families. Busier in the middle of the day.
Tamarind Bay
A small, quieter beach just north of Mushroom Bay. Usually calm.
Jungutbatu
The long main beach. Swim at mid to high tide; at low tide the water drains off the reef and seaweed. Watch for boats and moorings.
Sandy Bay
A small cove on the south-west coast, beautiful in the afternoon. Waves can be strong; swim only on calm days.
Secret Beach, Ceningan
A hidden cove on Ceningan. Calm days only; the waves can be powerful.
Dream Beach
The most photographed beach, and the one with the strongest shore break. Waves dump onto the sand and pull back out. Swim only when it's flat.
How the tide changes things
At low tide, the channel-facing beaches can turn into shallow reef flats, great for exploring in reef shoes but not for swimming. At high tide they fill up again. On the south-west coast, high tide with a big swell is when the waves are most dangerous. Check a tide table each morning.
Before you swim
Watch the water for a few minutes first. Look for where locals swim. If you can't see the bottom or the waves are dumping, stay on the sand. More on the south-west coast.
Questions
Which beach on Nusa Lembongan is best for swimming?
Mushroom Bay, a sheltered bay on the west coast. Tamarind Bay and Jungutbatu are also good at mid to high tide.
Can you swim at Dream Beach?
Only when the sea is completely flat. Dream Beach has a strong shore break and can pull back out. On most days it's best enjoyed from the sand.
Are there rip currents on Lembongan?
Yes, especially on the south-west coast and wherever there are waves. Swim where locals swim, at calm beaches, and never alone.
Header photo: Aurelia Teslaru, CC BY-SA 4.0, via Wikimedia Commons
Yellow Bridge and Ceningan
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