High Speed = Rail Europe, map:

• https://www.raileurope.com/plan-your-trip/travel-ideas-and-itineraries/
• journey-builder: https://www.raileurope.com/spip.php?page=journey_builder
• Very useful train-travel resource= The Man in Seat 61 (www.seat61.com) (france specifically)
• Get Eurail as Americans but expensive:

Passes must be validated at a train-station ticket window before you begin your first journey.