You Can Walk on the Ocean Floor in the Netherlands — Here's How

The Sea Disappears. And You Can Walk Where It Was.

Twice a day, something extraordinary happens along the northern coast of the Netherlands. The North Sea retreats, and in its place appears a vast, shimmering landscape of sand and mud stretching all the way to the horizon. This is the Wadden Sea — a UNESCO World Heritage Site and one of the most remarkable natural environments in Europe.

And yes, you can walk on it.

What Is the Wadden Sea?

The Wadden Sea is the world's largest unbroken system of intertidal sand and mud flats. It stretches 500 kilometres along the coasts of the Netherlands, Germany, and Denmark. When the tide goes out, up to 250 square kilometres of sea floor are exposed — creating a surreal, almost alien landscape.

This tidal system supports an ecosystem of extraordinary richness:

• 10–12 million migratory birds stop here annually
• Thousands of seals live on the sandbanks
• Marine life — shrimp, crabs, shellfish, and fish — thrives in the shallow waters

In 2009, it was inscribed as a UNESCO World Heritage Site — in the same category as the Great Barrier Reef and the Galápagos Islands.

Mudflat Walking: The Experience

Wadlopen (mudflat walking) is a uniquely Dutch experience. With an experienced guide, you walk out onto the exposed sea floor, sometimes for several kilometres, experiencing a landscape that exists for only a few hours before the sea returns.

What it feels like:

• The mud is warm and alive beneath your feet
• Shallow channels of remaining seawater must be waded through
• The silence is profound — nothing but wind, birds, and your own footsteps
• The horizon is impossibly distant in every direction
• You're walking where, hours ago, ships were sailing

What you see:

• Lugworm casts creating patterns in the sand
• Cockles, mussels, and razor clams
• Crabs scuttling between tidal pools
• Seals in the distance on sandbanks
• Migrating birds by the thousands

Important: Never walk the mudflats without a certified guide. Tides are powerful and the landscape is disorienting.

Droogvallen: When Your Ship Becomes a Viewing Platform

Here's something most people don't know is possible: some ships in the Wadden Sea intentionally "droogvallen" — they let themselves settle onto the sea floor as the tide goes out.

Ship Josefien regularly does this. Here's what happens:

• Evening: The ship anchors in a shallow part of the Wadden Sea
• Night: As you sleep, the water slowly recedes
• Dawn: You wake up and look out your porthole — not at water, but at an endless expanse of glistening sand
• Morning: You step off the ship directly onto the sea floor. The silence is breathtaking
• Activity: Collect mussels, walk the flats, watch the sunrise. Some guests describe this as the highlight of their entire trip
• Midday: The tide returns, the ship lifts, and you sail away

Guests consistently describe droogvallen as a once-in-a-lifetime experience. You are standing on the bottom of the sea, with your ship resting beside you like a beached whale, surrounded by nothing but sand and sky.

Seal Spotting

The Wadden Sea is home to both harbour seals and grey seals. From the deck of your ship, you'll see them:

• Basking on sandbanks during low tide
• Swimming alongside the ship as you sail
• Nursing their pups (June-July) on protected sandbanks

Binoculars are recommended, though seals often come surprisingly close to ships.

The Wadden Islands

The Dutch Wadden Islands form a string of barrier islands between the Wadden Sea and the North Sea:

• Texel — The largest, with forests, beaches, and breweries
• Vlieland — Car-free paradise for nature lovers
• Terschelling — Arts, culture, and diverse landscapes. Host of the famous Oerol festival
• Ameland — Historic villages and a climbable lighthouse
• Schiermonnikoog — Smallest inhabited island, entirely a national park

Ship Josefien's Wadden Sea routes include visits to these islands, with time to cycle their landscapes and explore their villages.

Experience the Wadden Sea from Ship Josefien

The most immersive way to experience the Wadden Sea is from a ship. You don't just visit — you live on the water, sailing through tidal channels, anchoring in remote spots, and waking up to experiences impossible from land.

Ship Josefien's Wadden Sea voyages run June through August. Maximum 22 guests. These are the first dates to sell out each year.