A Dover to Calais crossing can be over before you've finished your coffee. Sail overnight from Newcastle to Amsterdam, or take the long run down to Santander, and the same ship becomes your base for a day or more. The packing list barely changes. What changes is how much you'll want within arm's reach.

Pack for the crossing, not just for the destination. A few minutes of thought at home saves queuing at the on-board shop, and it's the difference between stepping off the gangway fresh and stepping off it grumpy, stiff and hungry with four hours of motorway still ahead of you.

What follows is the list we come back to every time: fifteen things that earn their place in a rucksack or cabin bag, whatever the route.

Why Ferry Packing Is Different

On most UK sailings the car deck is sealed shortly after departure, and you can't go back down to your vehicle until the crew announce that it's open again. That single rule changes everything. You cannot nip to the boot for a jumper, a phone charger or a child's favourite teddy — whatever you need for the next ninety minutes or the next thirty hours has to come up the stairs with you.

Cabins are compact, too. Expect a bunk, a small shelf or two, a hook on the back of the door and not much else. A bag that sprawls across the floor will trip you up at 3am on the way to the loo, and there is rarely anywhere clever to stash it.

And while the on-board shop and self-service restaurant are genuinely useful, they are busiest at exactly the moments you're hungriest, and opening hours can shift with the sailing. A modest bag of your own supplies costs very little and takes the guesswork out of it.

Rule of thumb: if you can't carry it up the stairs in one trip, you've packed too much for the crossing — and not enough for the journey.

The 15 Things to Pack

Documents and Boarding Paperwork

• 1. Passport (plus any visa or ID card you need). Check the expiry date before you book, not at the check-in barrier. Some destinations ask for six months' validity beyond your return date.
• 2. Booking confirmation and boarding paperwork. Screenshot it as well as saving the email. Port signal can be patchy, and the reference number is what gets you through the gate. If you're travelling with a pet, add the Pet Travel Scheme documents and vaccination record to the same folder.

Comfort and Sleep

• 3. Layers and a warm jumper. Decks at dawn are cold, cabins can be stuffy, and the restaurant sits somewhere in between. A light fleece and a scarf cover all three.
• 4. Travel pillow. Even a proper cabin bunk usually comes with a thin, plasticky pillow. On a reclining seat, a neck pillow is the difference between dozing and a stiff neck.
• 5. Eye mask and earplugs. Engines hum, cabin doors bang, corridor lights bleed under the gap. These two small items are the cheapest upgrade to any overnight sailing.
• 6. Soft shoes or slippers. Deck surfaces get slippery when wet, and shared shower floors are no place for bare feet. Something you can kick on and off is ideal.

Food and Drink

• 7. A refillable water bottle. Fill it at the terminal or from a tap on board. Buying bottled water for a family of four across a long crossing adds up fast.
• 8. Snacks. Nuts, fruit, oatcakes, a couple of sandwiches made at home. Overnight sailings are long, and the gap between dinner and breakfast is longer than you think.
• 9. Tea bags or coffee sachets and a travel mug. Many cabins have a kettle; if yours doesn't, hot water is usually available in the self-service area. A mug with a lid is far safer than a paper cup on a moving ship.

Power and Entertainment

• 10. Power bank. Phones burn through battery when you're filming the White Cliffs or refreshing the weather forecast. Charge it at home and leave it in your day bag, not your suitcase.
• 11. Chargers and a travel adapter. Cabins typically offer one or two sockets, often UK three-pin on UK-flagged ships but not always. A small multi-USB plug or short extension lead lets everyone charge at once.
• 12. Headphones and something offline. Download films, podcasts and audiobooks before you board — on-board Wi-Fi is often slow and sometimes paid. A paperback still works when the signal doesn't.

Health and the Morning After

• 13. Seasickness tablets. Buy them before you sail and take the first dose about an hour before departure, as the instructions advise. They work far better as prevention than as a cure.
• 14. A small toiletry bag. Toothbrush, deodorant, wet wipes and any prescription medicine you take regularly, kept in the bag you carry rather than the case in the car.
• 15. One change of clothes in your carry-on. A clean T-shirt, socks and underwear turn a long crossing from endurance into a proper reset, and they cover you if the luggage stays behind.

Packing for Different Crossings

• Short hops — Dover to Calais, Holyhead to Dublin, Cairnryan to Belfast. Treat it as a long train journey. A small backpack with water, snacks, a charger and a book is plenty; there is no point dragging a suitcase upstairs for ninety minutes.
• Overnight crossings — Newcastle to Amsterdam, Hull to Rotterdam. Pack as though for one night in a hotel. Add sleep kit, a wash bag, a change of clothes and something to do before bed. Keep the main luggage in the car and take only what the night requires.
• Long sailings — Portsmouth to Santander, or any crossing of a day and a night. This is a mini cruise. Layer your bag: essentials on top, entertainment in the middle, a full change of clothes at the bottom. Consider a small extension lead and a couple of extra snacks per person.

What Can Stay in the Car

Because the vehicle deck is closed for most of the crossing, anything left in the boot is effectively in storage. That's fine for the bulky, the dirty and the replaceable.

• Full-size pillows, duvets and beach towels.
• The rest of the holiday wardrobe, suitcases and anything you won't touch until you reach your destination.
• Wet-weather gear that can wait, spare shoes and the picnic hamper for the drive.

Keep your passport, tickets, medicines and valuables with you, though — not least because you may want your paperwork to hand before you're allowed back to the car.

Get these fifteen things right and the crossing stops being a gap between two drives. It becomes the part of the trip you look forward to.

Photo: Craig Adderley / Pexels