Mljet National Park: the greenest island in the Adriatic

An island that earns its superlatives

Mljet is the most forested island in the Adriatic. Around a third of its surface is protected as a national park, and the dominant impression — whether arriving by catamaran, cycling through the interior, or swimming in one of the two saltwater lakes — is of dense, unbroken greenery reaching down to impossibly blue water. The comparison to Brijuni or Plitvice is tempting, but Mljet has a coastal character those parks lack: the seascape is always present.

The national park occupies the western third of the island and contains the main reason people come: Veliko jezero (the Great Lake) and Malo jezero (the Small Lake), two shallow saltwater lakes separated from the open sea by narrow channels. At the centre of Veliko jezero sits a small islet, St Mary (Sveta Marija), with a 12th-century Benedictine monastery that has been converted into a restaurant — one of the more unlikely and atmospheric lunch spots in the entire region.

Away from the lakes, the western end of the island also has the Odysseus Cave (Odisejeva špilja) near Babino Polje: a sea cave with associations to the Odysseus myth (the precise connection is uncertain and somewhat embellished in tourist literature, but the cave itself is genuinely interesting) and a beach that gets strong afternoon light.

Why Mljet is worth the longer journey

Mljet takes about 1.5 hours by catamaran from Dubrovnik — significantly longer than the Elaphiti. That travel time is the honest price of admission. What you get in return is an island that remains relatively uncrowded compared to its reputation, primarily because organised day trips from Dubrovnik tend to arrive in concentrated waves before dispersing into the park. Cycling the lakeside paths first thing in the morning or late afternoon, when tour groups are eating or boarding their boats, gives you the national park almost to yourself.

Be honest with yourself about timing: a day trip to Mljet can feel slightly rushed. You have about 6–7 hours on the island on a typical organised tour, and the national park alone rewards 3–4 hours of exploration. If you want to swim in the lakes, walk to the monastery, visit the Odysseus Cave, and cycle some of the lakeside path, you will need to move efficiently. Staying overnight in Pomena or Polače — the two small villages inside the national park — transforms the experience entirely.

The Mljet National Park guide covers the park in more detail, and the Korčula-Mljet-Pelješac loop itinerary shows how to combine Mljet with the rest of the region over several days.

Top things to do on Mljet

Swim in the saltwater lakes. Malo jezero and Veliko jezero are the defining experience of Mljet. The water is warmer than the open sea (the lakes heat up faster) and exceptionally clear. There is a small beach at Mali Most — the bridge connecting the two lakes — that is the most popular swimming spot. Arrive early in July and August.

Take the organised national park day tour from Dubrovnik. The standard day trip from Dubrovnik includes the catamaran crossing, national park entry, and a boat transfer to the island monastery. It is a well-run option that handles logistics efficiently.

Cycle the lakeside paths. Rental bikes are available at the park entrance near Polače (around €8–12 for a half-day). The flat circuit around Veliko jezero is 8 kilometres and takes 45–60 minutes at a relaxed pace. Some sections pass through dense pine forest with occasional lake views — it is one of the best cycling routes in South Dalmatia.

Visit the Odysseus Cave. The cave near Babino Polje is accessible by local boat from Polače (the operator near the harbour runs trips throughout the day in season). The cave has a narrow sea entrance that opens into a domed interior with a swimming platform — impressive even if the Odysseus mythology is mostly invented.

Take a private speedboat from Dubrovnik. For groups who want flexibility — arriving and leaving when they choose, choosing their own swimming spots — a private speedboat tour covers the Mljet highlights without the schedule constraints of organised day trips.

Have lunch at the monastery on St Mary islet. The 12th-century Benedictine monastery on the islet in Veliko jezero now operates as a restaurant (Konoba Melita or similar, depending on the season). The short boat transfer from the lakeshore is included in most day tour packages. The food is unremarkable for the price (expect €20–35 per person for a full lunch), but the setting is exceptional.

National park entry

Entry to the western part of Mljet (the national park) costs approximately €18–25 depending on the season (peak summer rates are higher). This fee is usually included in organised day tours. If visiting independently, pay at the park entrance near Polače. The fee covers access to the lakes and the national park path network; the boat transfer to St Mary islet is an additional small charge (around €3–5 return).

Where to eat on Mljet

Most visitors eat at Konoba Melita on St Mary islet, the restaurant inside the former monastery. It is convenient, atmospheric, and overpriced given the quality, but worth it once for the experience. Book your table in advance in peak season — spaces on the islet are limited and tour groups fill them early.

In Polače (the main entry village), a couple of waterfront restaurants serve grilled fish and Croatian standards. Restaurant Stermasi has a pleasant terrace and reliable fish dishes (mains €16–25). The village is small but the waterfront is genuinely pretty.

Pomena, the other national park village, has similar options. Its position on a sheltered bay makes it a calmer and slightly more atmospheric base for an overnight stay.

How to get to Mljet from Dubrovnik

The fastest and most reliable option is the Krilo catamaran (operated by Kapetan Luka), which runs from Gruž harbour in Dubrovnik to Polače and Pomena. Journey time is approximately 1 hour 30 minutes. There are typically one or two daily sailings in each direction during peak season — check the current schedule at krilo.hr as times change each year.

The Jadrolinija ferry also serves Mljet but takes longer and docks at Sobra on the island’s eastern end, outside the national park. From Sobra you would need local transport or a long taxi ride to reach the lakes — not practical for a day trip.

From Dubrovnik’s Old Town to Gruž, take bus 1A or 1B (about 20 minutes) or a taxi (€10–15). The ferries and catamarans guide has up-to-date scheduling information. Mljet also features in the South Dalmatia 7-day no-car itinerary as a natural overnight stop.

Frequently asked questions about Mljet National Park

Is Mljet worth the trip from Dubrovnik?

Yes, particularly if you appreciate natural scenery over historical attractions. The combination of forested landscape, saltwater lakes, and the monastery islet is genuinely unlike anywhere else in Croatia. The longer journey time (compared to the Elaphiti) means fewer casual visitors, which helps preserve the atmosphere.

Can you visit Mljet without a tour?

Yes. Take the Krilo catamaran to Polače, pay the national park entry fee (€18–25), hire a bike at the park entrance, and explore independently. The main disadvantage is that catamaran timing forces an early arrival and a fairly specific departure — missing the last boat back to Dubrovnik would leave you stranded overnight (which some people would consider a bonus).

Are day trips to Mljet rushed?

Honestly, yes — a bit. With around 6–7 hours on the island, you can do the lakes, a swim, and see the monastery, but not linger as long as you might like. The island genuinely rewards an overnight stay: waking up in Pomena or Polače when the tour groups have not yet arrived is a different experience entirely.

What is the national park entry fee?

The fee is approximately €18–25 per adult depending on the season, with discounts for children. The peak summer rate typically applies from July 1 to August 31. This fee is included in most organised day tour prices from Dubrovnik — check before booking.

Is swimming in the lakes safe?

Yes. The lakes are calm, shallow (Malo jezero averages about 9 metres deep, Veliko jezero about 46 metres), and the water quality is excellent. There are no jellyfish problems in the lakes that plague the open sea in some seasons. The lakes do not have dedicated lifeguards, so swim with awareness.