For a bit of a unique experience, I really recommend Gibraltar. Nestled into a massive rock, surrounded by sea and Spain, this UK territory (with right-side-of-the-road driving) is seriously interesting.
We really liked Gibraltar. Note that you need a passport (unless you are an EU citizen) to enter into the UK territory. Gibraltar has a rich history dating back hundreds of years, under the occupation of the Moors, Spanish and then the English. The population is 30,000 and we found that many of its inhabitants have been there for many generations – crammed into the side of its huge rock. We took an excursion with Gibraltar Rock Tours up the rock where we were taken to see The Pillars of Hercules [the end of the flat earth], St. Michael’s caves with amazing stalactites, The Great Siege tunnels and then of course, to see the monkeys [Barbary Macaques]. The monkeys are believed to have come from Africa, brought by the Moors. Winston Churchill once famously said during WWII, ‘as long as the monkeys exist on Gibraltar the territory will remain under British Rule‘. I guess that’s fine, as long as those suckers remain at the top of the rock because they quickly became annoying, climbing all over you, on the cars, in the cars…
Take time to stroll through the main town, where you can find stores typically only found in the UK and traditional English pubs. The main drag is a pedestrian-only street and flat (nice, since the rest of the place is very hilly). Shopping in Gibraltar is tax-free – major bonus.
Other activities on the island include walks, hikes, fishing and whale watching tours and of course, beach time. There is an abundance of business in Gibraltar which has definitely influenced its nightlife scene…which is pretty vibrant. There is a casino too!
As for transportation. We had a car which was relatively easy (though a bit of a pain with boarder control). If we hadn’t had a car then I think walking would be been the next best option, as the area is small and most main attractions are close together with the exception of those on the rock itself. I remember seeing taxis but not recall any (or much) public transportation.
Now getting there – Gibraltar makes you realize how huge Spain is. A drive will take you approximately 8 hours. One option is to take an Iberia flight to Sevilla and rent a car for the short drive south. Or fly directly in with Easyjet and British airways (may be difficult from Madrid). And then there is always the Renfe trains which you can take to neighboring Algeciras and take a short taxi to the boarder.