The Panama Canal is an engineering wonder of the modern world. Negotiating it is also a challenge

For all its mere 50 miles, few waterways claim a more pivotal role in the world of international trade and seafaring legend than the Panama Canal. Since its completion by the USA in 1914 – an earlier French attempt ended in disease and bankruptcy – it has offered safe passage from the Caribbean to the Pacific through the heart of Central America, a short cut of some 5,000 miles. As an object of geographic and economic interest, a feat of engineering ingenuity and a focal point of world shipping it is as impressive and relevant today as ever.

I am not the world's most experienced yachtswoman; even so, I realised sailing the Panama Canal would not be as simple as sticking on the engine and heading southwest for 11 hours. There are six locks to negotiate for a start. What I hadn't conceived was the staggering contrasts of the transit from mangrove swamp at the Atlantic, through a tropical lake, a deep gorge and finally the sweeping entrance to the Pacific's Gulf of Panama, marked by the arching Bridge of the Americas linking South and Central America.

By the time my three fellow crewmates and I reached Panama we had been at sea for eight weeks. Barely having stepped on a sailing vessel before, I had managed to cadge a berth on a yacht delivery from France to Mexico's Baja California. The appointment was made solely on the premise of my gender and inexperience: the skipper always likes to take one woman, although I'm not sure I ever discovered why, and my incompetence gave him someone to shout at.

Day after day of listless sea talk had left me in no doubt as to the magnitude of what we were about to undertake. Neither had the initiation element of the Panama Canal passed me by. By the time we reached the far side, I would still be as green a sailor as they come – seasickness continues to dog me on everything from rowing boats to cross-channel ferries – but I would at least have one nautical trophy on my side.

Confident I was not; it had taken me that time to get to grips with my bowline, a knot eight-year-olds muster in minutes. Yet now the fate of a new 50ft luxury Beneatau rested heavily on my, and my three fellow line-handlers' knot-tying abilities.

The night before our scheduled 5am transit we moored on a buoy in Limon Bay near the canal approach. From the grey mist of the pre-dawn sea our adviser for the day Peter, an American Panamanian, and his apprentice Mr Chan, chugged into view on a canal authority boat and clambered aboard. It was Peter's job to ensure the good ship Silvia – named by Swedish crewmember Matthias in deference to his queen – completed this stage of her 7,600-mile journey in one piece. We were on strict orders from the captain to be exceedingly nice. We even opened the cockpit awning for the first time (having previously resorted to tying a sheet above the helm to keep the midday sun off lest we damage the boat's fixtures before delivering her).

Since Spain's Charles I commissioned a survey in 1534 for a waterway between the oceans, the Panamanian isthmus has been the focus of fraught international wrangling. The Panama Canal Zone, a corridor five miles either side of the channel, reverting from the USA to Panama only in the final hours of 1999. So it is no surprise that securing and completing a Panama Canal transit is a complicated affair. A mass of form-filling and inspections had had us hanging around the dilapidated port of Colón for days. Finally, we were on our way, but the onus was still on keeping sweet the powers that be.

Peter, encouraging but unconvinced, issued instructions over plastic mugs of tea as we motored slowly between the huge container ships that had been our dorm mates, and into a wide mangrove creek. The mood onboard was expectantly sober as we made our way into the channel. Above the gentle pump of the engine the swamp's assorted wildlife stirred into their early morning routines. Meanwhile, Lorenzo, our additional line-handler – commandeered for the day from the yacht club – snoozed below. The day before, he had acquired for us the necessary four lock-manoeuvring ropes, each 125 feet long. They lay neatly coiled in lockers beneath the deck seats.

After an hour we reached Gatun Locks, a flight of three steps that raises boats 85 feet into Gatun Lake. Like a shiny piece of flotsam, we entered the first gates on the tail of a vast container ship. As our vessel nestled in behind, we line-handlers got into position, me aft portside within skipper Roger's shouting range.

After weeks and thousands of nautical miles of talk, it was time for action. Line-handlers on the lock walls above threw ends of rope to attach to our lines to secure the boat from above. As the gates closed behind us, the water came and we rose gently upwards. Eight minutes later the lock was full – a textbook operation.

On to the next lock, the atmosphere on board mightily relieved by our demonstration of professionally harmonious seamanship. Roger suggested it was time to get the beers out, not for us on board but as a gesture of goodwill for our landside friends. It may have been pure bravado on his part – Lorenzo looked none too chuffed that the beers he was planning to tuck into were disappearing overboard – but those few cans tied in plastic bags to the lines certainly helped us out of a sticky situation when the line I was feeding to my opposite on the wall ran short. Held securely in all corners bar one, the boat veered dramatically to the right. In a flash I realised the inadequacy of my failed RYA level two dinghy certificate. Panic-stricken, I watched helplessly as Roger, leaving the helm for the mere fleeting of a second, delved into a locker for a rope and performed a split-second bowline.

Meanwhile, my landside opposite peered down about to drop the line leaving us to our fate when he spotted the bag dangling tantalisingly out of reach – his pals had already landed theirs. It was the delay we needed to get the additional rope attached and resume our controlled ascent. With everything back on course, we negotiated the third lock without a hiccup. Meanwhile, the rope-skimping Lorenzo sneaked back down below for a kip.

As Lorenzo dozed, we got the sails up and made our way into Lake Gatun, an expanse of deep blue water dotted with islands of trees and the dark stumps of long submerged jungle. For all its commercial and strategic significance, Lake Gatun seems more of a large boating lake – albeit with very large boats – than an industrial waterway. Neither is there any reminder of the 24 Panamanian villages that lie at the bottom of what is the new floodplain of the Chagres River.

The 23-mile crossing was a relaxed affair and gave us time to impress Peter with our culinary expertise. But before the trio of locks that lowers vessels down to the Pacific, it was necessary to negotiate the Gaillard Cut, an eight-mile channel carved through rock and shale. It was here that the most demanding digging was required. Devastating and often fatal slides occurred during construction and after the canal was opened. There is something chilling about being hemmed in by those grey stone walls. By the time we sat nursing our first beer of the evening at the Balboa yacht club I had my own Panama Canal yarns with which to bore any salty dog that was prepared to listen.

It is possible, in theory, to pick up work as a line-handler at the yacht club at Colon (the one in Bilbao has burned down since the writer made her transit). Alternatively, tour operators in Panama City organise boat trips on the Canal. More info: 'Panama' (Lonely Planet, second edition, £10.99)