I do think Jerez is a jewel. I've stayed there a total of four nights in the pst two years and will go back next winter.
Gorgeous architecture, amazing amount of high quality restaurants for a city of its size, lots of greenery, piazzas with cafes, the sherry bodegas, the horse show, and most of all, the warm and welcoming people.
Not to mention one of the finest hotels in Andalucia.
Sanlucar is, to me, a charming town on the river with a great, vital main plaza and a strip of wonderful restaurants along the river, walking distance from the Centro. It comes alive at night, so if someone has been only during the heat of the afternoon, its appeal might be elusive, I think. it's also a jump off point for the trips into the Donana National Park. And there are those sweets baked by the nuns in the convent de Santa Clara...buying those is a real experience; you can do this in Sevilla, too, of course, and in other towns and cities.
If you are in the area during almadraba (but its in May) I would see if you can partake of this once-in-a lifetime experience; you'd have to sign up for a tour, which would be weather dependent. People from all over Spain and beyond flock to the four towns on the route to taste the bluefin in all its various guises..... It's a party atmosphere
but also allows the opportunity to witness the capture of the tuna using methods dating back to the Phoencians. The four town of the almadraba--Tarifa, Zahara, Conil and Barbatee (each are quite different from one another)..together are probably found zero for aficionados of bluefin tuna. May Japanese come to this area to eat at the legendary tuna restaurants, of which the most famous is EL CAMPERO in Barbate. Even if you are in the area in May, if you have any interest in food, you will want to have at least one meal there....
But that's just one highlight of this area; this is all within the Province of Cadiz and, for me, one of the most beautiful parts of the province is the area called La Janda, with Vejer de la Frontera as its main inland focus. Although the town is not well known to the average North American travelers, along with a few nearby hamlets and towns, it's one of the food meccas of southern Spain and the scenery, hills, beaches, meadows, around there take my breath away. I'm admittedly biased, and I keep returning. The town of Medina Sidonia is known throughout Spin for its pastries and its glorious 'white' architecture but when I went a few weeks ago, there wrecked no tour groups and no one speaking a language other than Spanish in one of the 'Venta" restaurants that have fame throughout the area. Each town even has its own food specialties!
it's just a totally different scene than places like Ronda and Arcos which are no doubt handsome but so much a part of the tourist trail that for em, the draw is no longer there. if you do go to Ronda, at least stay overnight; there are some very good restaurants and places to take in the views.
But there are also so many towns that get almost no mention here that also have grand scenery, white cubist architecture, views from the heights, etc etc.....but since they do not get mentioned in many English-language guidebooks, they do not draw the day trippers and the tour groups.
As Jamie says, it depends on what you are looking for.....
Even in Seville, you can surround yourself with the tourist following their leader's little flags, or you can wander around in areas that seem, to me at least, to represent the Spain of the yers perhaps before this current Insta-selfie age.... And Jerez for whatever reason, apart from the bodegas and the horses, is just a charming Andaluz city where a visitor is seen not just as one of many but as a valued guest. This all sounds very sappy but that's th experience I've had in those places nd that's part of the reason I keep going back, although by now I've visited most of the more obvious regions of the country.
