Hey Lurch!
The possibilities are endless. As mentioned by some forum members , you can actually start anywhere.
The Santiago to Madrid route is covered by a very efficient train service.
Try starting at Segovia which is a lovely city both in architecture and cuisine then walk towards Madrid. You will climb up the mountain though, a lovely trek I am sure you will enjoy. You will be in Madrid in 4 days using the Gronze stages. If you run out of time , just hop on the train or bus to Madrid.
Have fun!
By the way, that's me on the Gronze webpage for the CdM. Resting on my way to Puente Duero (April 2017). I had the privilege of walking with Carles, "un caminante muy amable" y un gran escritor"
All the best! Buen camino!
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