Spending days at sea in the choppy waters of the Bay Of Biscay might be some people’s idea of a nightmare. But, despite my tendency to get seasick, I’d always been fascinated by that marvellous feat of engineering – the cruise ship.

The height of an 11-storey block of flats and stretching 177m in length, the majestic Pride Of Bilbao was waiting in Portsmouth Harbour for her passengers to board.

Inside, the gold stairwell banisters and burgundy decor give the ship a classic feel and before we departed there was time to explore our cabins.

To my delight, a window offered a view out across the ocean, but the club-class accommodation was of a basic standard. Nonetheless, the cabins provided a comfortable space to retire to if the motion of the ship became too much.

After unpacking, we were led to the Four Seasons carvery to select our fare from the massive range on offer. Not used to such choice, I had difficulty narrowing my selection down to what would fit comfortably in my stomach.

Minutes later, the ship’s engines rumbled to life and we began to back out of the harbour. Out on deck, looking down at the dark waters of the English Channel bubbling past, I was filled with a childlike sense of glamour and adventure.

After a comfortable night’s sleep and a short time out on deck to take in the morning air with a cuppa, we were invited to watch a presentation by a team of volunteers from the Biscay Dolphin Research Programme (BDRP). Although all passengers are free to spend time hanging over the decks in an attempt to spot dolphins, paying the extra cash to take part in the proper cetacean-spotting activities is recommended.

We were then given a tour of the ship’s main floors, which contains everything needed for a short break, including bars, two restaurants, several places to buy snacks and coffee, a tax-free shop, a casino, a children’s play area, a gym and two cinemas.

Out on deck, the sun was hot and the sky was cloudless – perfect conditions for dolphin spotting, and ideal for those on board whose only plan of action was to sunbathe.

Since our only stop would be a three-hour mooring in the port town of Santurtzi, just outside Bilbao in the Basque region of northern Spain, it was expected that some passengers would use the voyage simply as a means to take advantage of the ship’s cheap alcohol and tobacco. And why not? With Britain’s notoriously high tax, it was little wonder the Pride Of Bilbao had attracted some “booze cruisers”.

Later that night, we checked out the ship’s Silverstone Bar. With cheap drinks and a different show each night, this was the place to catch performers recreating scenes from West End shows.

If such typical cruise ship entertainment is not to your taste, the POSH bar upstairs offers a quieter place to enjoy a drink, with the gentle accompaniment of a pianist.

Once again, I rose early to catch the sunrise as the ship made its way towards Santurtzi. Standing out on deck, the view was spectacular as the steel greys of parting clouds gave way to brilliant orange rays.

Following another hearty breakfast, we disembarked from the ship for a walking tour of the modern, yet gothic, city of Bilbao. Fabulous architecture lines the city’s Nervion River, including the Frank Gehry-designed Guggenheim gallery, and the traditional cobbled backstreets. I would have loved more time to explore.

Back on board, the view of Spain’s mountainous green landscape provided the perfect backdrop as we set sail for the return journey to Portsmouth.

Further whale and dolphin spotting filled the remainder of the day, and I was delighted to see the dorsal fin of a Cuvier’s beaked whale as it arched out of the water in preparation for a dive.

Later, an announcement was made to alert passengers to a dolphin pod about to reveal itself in the ship’s wake. Clearly visible to the naked eye, several common dolphins gracefully charged through the water at high speed and leapt through the air as they enjoyed a “knees-up” in the waves beneath us.

There were also sightings of several whale blows, where water and mucus could be seen rising in the air from a distant mammal’s nostril. Captain McFadyen, whose pride in the ship was infectious, had to make an emergency turn to avoid a collision with two sperm whales sighted ahead.

The experience of seeing whales and dolphins was soothing, and I could happily have remained on board the Pride Of Bilbao for much longer. The Bay Of Biscay is an ideal destination for a short break and I was sad to disembark for the final time.

* Nicole travelled on a return cruise from Portsmouth Harbour to Bilbao with P&O Ferries. Voyages run all year round and prices, including three nights’ accommodation in an en-suite cabin, start at £87 per person.

* Spanish excursions, including a tour of Bilbao, a Guggenheim visit and a trip to a fishing village, can be booked on board for an extra cost.