I had us on the road before my wife could object that we didn't have a decent road map. No one does in Croatia. The one you get from the tourist board is primarily intended to confuse the Serbian army, not help tourists to navigate their way up Croatia's beautiful but splintered coastline.
"It looks as if someone's broken bits off," said Kate and she had a point. The Dalmatian coast is fractured into long shards of islands and peninsulas that hug the shore so closely that you often can't tell until you arrive whether it's a peninsula you're heading for or an island that will require a ferry crossing.
We found the E65 out of Dubrovnik without any difficulty and almost sailed over the graceful Dr Franjo Tudjman Bridge, except at the last moment Kate lost confidence in our minuscule road map and sent us off inland in search of Bosnia-Hercegovina. A frosty marital silence ensued as I executed a three-point turn, and it continued until I admitted that it was all the map's fault.
Regaining the mighty steel bridge, we headed north watching white ocean liners below. The Dalmatian coastline has a rugged beauty, mountains rising up on our right and unbearably blue sea below. Tree-topped islands lined the entire route, with just an occasional Baroque spire thrusting up through the foliage.
At Doli we turned off on to the panoramic route through Peljesac. Looking at the map Kate had thought this was going to be an island but it turned out there's still a few inches of terra firma either side of the road connecting this stunning 65km-long peninsula to the mainland.
An oyster farm lay below us in Mali Ston Bay. This turned out to be part of a unique environmental experiment between Croatia and Bosnia. Ostrea edulis, the small round oyster farmed here, was once common all round the world but a plague in the 1930s wiped them out in Japan, California and France. Those in Mali Ston Bay survived, however, and scientists found that its ecological balance - salt water fed by freshwater springs, stirred by a regular wind - is crucial for Ostrea edulis to survive. So keen are the Bosnians and Croatians to preserve these last remaining oyster beds that both countries have agreed not to build anything near Mali Ston Bay, not even a hotel.
We tried a few but, sadly, they don't compare with the cold-water oysters of Brittany and Scotland that we love. Too small. Too dry. Still, we wished them well and within a few kilometres we were at Ston, a curiously castellated town with walls running almost vertically up the hillside behind it. They've been there for more than 1,000 years and link 41 towers. Seeing as most of what was enclosed looked like fields, I assumed that Ston had shrunk somewhat since its heyday as a vital salt-panning centre on the Croatian coast.
"There's a governor's palace worth seeing which dates from when Ston was a satellite of the Republic of Ragusa," I said, but Kate didn't want to stop. Having been thrown by Peljesac's refusal to be an island she needed to prove herself. So we headed down the spine of this sunken mountain range with Orebic firmly in my wife's sights.
"Ooh, that's a winery," I said from time to time. For indeed this is a major wine-growing country.
"Let's just get there," Kate replied, her head in the map, as we shot past vines with improbable names such as Postup, Posip, Dingac and Plavac, and also, no doubt, great tastes.
Orebic turned out to be a charming village, home to some of the most accomplished sea captains in this stretch of the Med. In the 19th century they built their homes along the road that leads down to the harbour. Here we found lots of Croatians waiting in their cars because, as Kate had correctly predicted from our micro-map, the only way to get from Orebic to Korcula is by ferry. People were diving off the quayside while they waited for the Jadrolinija ferry to arrive and within a few minutes of switching off the AC we were in too. The water was spectacularly clear and wonderfully cooling.
Shortly after lunch, we made landfall on Korcula, a island notable for the fact that Marco Polo was born there, left and never came back. The old town is delightful, white, pantiled and fortified just like Dubrovnik. We had evidently just missed the Moreska, a sword dance performed by men dressed like chess pieces, which happens every Thursday during the tourist season, and in which Moors get soundly thrashed by Christian knights.
Frustrated, I was all for seeking out Signor Polo's house of which only the tower remains. It's supposed to give great views of the island. But we were waylaid by a restaurant en route. It's remarkable what the shade of some pine trees, a bottle of well chilled Posip and a view of the Peljeski channel can do for Ostrea edulis. We spent a long time over that meal and on the way back we threw the map away.
Adrian Mourby flew to Dubrovnik with Croatia Airlines (020-8563 0022, croatiaairlines.hr), which offers returns from £129. Holiday Autos (0870-400 0010; holidayautos. co.uk) offers one week's fully inclusive car hire on the Dalmatian coast from £119. For more information, contact the Croatian National Tourist Office (020-8563 7979, croatia.hr)
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