Sperlonga Blue Grotto Cruise: Swim, Snorkel & Ancient Caves

Summary

Blue water caves old Roman ruins and a swim in Sperlonga

You’ll set out from Sperlonga’s harbor with a local skipper guiding you past Roman ruins and medieval towers before stopping for a swim at the Blue Grotto. Dive into crystal-clear water or relax on deck while learning coastal legends. The gentle pace and salty air make this mini cruise feel like a real escape — one that lingers long after you return.

What’s the experience like?

I’ll be honest, I didn’t expect to feel so calm as we drifted out of Sperlonga’s harbor — maybe it was the way the sunlight bounced off the water or just hearing our skipper, Marco, chat about Grotta di Tiberio like it was his own backyard. He pointed at the old villa ruins tucked into the cliff and told us how Emperor Tiberius used to throw wild parties here. You could almost picture it, even with the sea breeze carrying a bit of salt and sunscreen smell. There were a few kids on board too, giggling every time someone mispronounced “Truglia.”

The boat moved slow along the Riviera di Ulisse Regional Park — which is good because there’s actually a lot to see. Medieval towers popped up between patches of green hills, and Marco kept tossing out little facts about Via Flacca (built in 187 BC!) that I probably should’ve remembered from school but didn’t. At one point I caught myself just staring at the limestone cliffs and thinking about nothing at all. That doesn’t happen much these days.

When we finally reached the Blue Grotto, everyone got quiet for a second — you know that hush when something feels special but you’re not sure why? The water looked almost fake, like someone turned up the color too high. I hesitated before jumping in (it’s cold if you’re not ready), but once you’re swimming toward those stalagmites inside the cave… well, it’s hard to explain. There’s this weird mix of echoing laughter and total silence under there. If you don’t want to swim, you can just hang back on deck — but honestly, I’d say go for it.

On the way back we passed Torre Truglia and caught a glimpse of Serapo Beach stretching out behind Gaeta. Marco joked that if we took enough photos we’d break his camera (he wasn’t wrong). I still think about that moment floating in spring-cold water with sunlight flickering above me — might sound cheesy but it sticks with you after.

Step-by-step itinerary

Day 1 — Mini cruise and swim at Blue Grotto

• Depart from Sperlonga harbour
• View Grotta di Tiberio and Villa remains
• Listen to historical commentary
• Sail along Riviera di Ulisse coast
• Admire medieval towers and Via Flacca
• Arrive at Blue Grotto for swim break
• Swim or snorkel near the cave
• Relax and enjoy crystal clear waters
• Return sailing past Torre Truglia
• Take photos of Torre Truglia and historic center
• Return to Sperlonga harbour and disembark

Top questions

How long does the Sperlonga Blue Grotto cruise last?

The cruise lasts around 2 hours including navigation and swim stop.

Is snorkeling equipment included on this tour?

Snorkeling masks are provided but guests must bring their own snorkel for hygiene reasons.

Where does the tour depart from?

The tour departs from Sperlonga's harbor near Torre Truglia.

Can children join this mini cruise?

Yes, infants and children can join; infants must sit on an adult's lap.

Is swimming in the Blue Grotto required?

No, swimming is optional; guests can remain on board if they prefer.

Are there shaded areas on the boat?

Yes, there is a curtain providing shade while seated on board.

What should I bring for snorkeling?

You should bring your own snorkel due to hygiene policies; masks are provided.

How do I get to Sperlonga's harbor if driving?

You can park at "Parking delle vite" and take a shuttle directly to the harbor area.

What’s included

Your day includes navigation with a local skipper who shares stories about Roman ruins and coastal landmarks, use of snorkeling masks (bring your own snorkel), shaded seating under a sun curtain, fresh water shower to rinse off salt after swimming in the Blue Grotto, pool noodles for floating comfort, and an easy-access ladder for getting in and out of the sea before returning to Sperlonga’s harbor.