u/p0tatotomato

I've recently had this idea that I want to walk a marathon - not part of an organised marathon, just going out for a day and walking 26.2 miles.

Wondering whether anyone had any recommendations for good routes or starting points?

I live near Warwick so starting point near there would be good. A loop would be good but it can also just be in one direction as I can get picked up.

I was thinking of just walking to Birmingham, but not sure how possible that is/whether the walk would be that nice?

Other option id thought of would be something along the Grand Union canal.

I'm currently on a British Gas EV Driver tariff, at 5.48p/kWh off peak. The tariff ends in a month, and the only tariff I can move onto with an off peak option is almost double the cost. What's my best bet for switching, Octopus? Or are there others I should consider?