This section of the Way of St James or Camino de Santiago, is also known as the Via Augusta, it is from Cadiz to Seville and is not the best part of Spain or Europe to make a pilgrimage through (although I accept that pleasure is not really the point of being a pilgrim). Too much of it is beside motorways and train-lines through suburbs with car dealerships and furniture stores, and country which various little and which the landowners' security measures made me feel unwelcome. That said the path does link the ancient cities of Seville, Jerez and Cadiz, with their beautiful old centres and historic buildings, as well as the food, wine and flamenco they offer. The other towns and villages the path goes through also have their quiet interest.
I would feel happier with more formal and abundant signposting and maybe a GR designation as elsewhere, this would have made it feel a more official trail. It is in the Andalucian government's interest to adopt the path as it clearly brings welcome business to places along the path, some information at tourist offices would be useful.
To follow this path there is a guide in Spanish on
http://www.asociaciongaditanajacobea.org/ and information on
http://www.csj.org.uk/planning-your-pilgrimage/routes-to-santiago/routes-in-spain/the-route-from-cadiz-to-sevilla/. The stages described are such that accommodation is available at the end of each stage in the form of hotels or rooms of some sort. I was able to use Booking.com to book my bed for each night, which avoided any language problems over the telephone. This is not camping country.
I used the gpx file from the following site
http://www.wikiloc.com/wikiloc/view.do?id=2406638, but should have read the notes associated with it more carefully (not easy when you are relying on a Google translation). However it was fine except for two sections.
From Seville to Dos Hermanas
Still not sure how I should have crossed the canal and motorway south of Seville without risking life on the side of the main road, maybe I should have been on the east side of the road. Having said that as much of the route is through urban areas it was not too difficult to find my way to Dos Hermanas (which Google insisted on always translating as "two sisters") even if it was not the most aesthetic route. I see that many people now follow the alternative route via Alcalá de Guadaíra instead of through Dos Hermanas.
From Utrera to Las Cabezas de San Juan
Many of the gpx files available on the internet follow a path that is likely to get you into trouble with the local landowner. The route in the following gpx file, which follows the railway line, avoids this and seems to follow the official route
http://www.wikiloc.com/wikiloc/view.do?id=11380202.