Directions

EuroStar (passengers only)
London St Pancras to Paris or Lille, then TGV to Poitiers where car hire is available
5-6 hours London to Poitiers

Ryan Air flies:
Stansted, Birmingham & Edinburgh to Poitiers, then 50 minute drive
Stansted, Liverpool, East Midlands, Bournemouth, Edinburgh, Bristol & Luton to Limoges, then 1 hour drive
Stansted & Dublin to La Rochelle, then 1h 30m hour drive

Fly.be flies
Manchester, Newcastle, Southampton, Belfast, Edinburgh, Glasgow, Guernsey & Jersey to Limoges, then 1 hour drive
Manchester, Newcastle, Southampton, Birmingham, Belfast, Edinburgh, Glasgow, Isle of Man, Kirkwall, Guernsey & Jersey to La Rochelle, then 1h 30m hour drive

Car hire is readily available at all airports without vast distances to walk.

Euro Tunnel (take your car)
Folkstone to Calais/Coquelles

LD Lines
Dover - Boulogne
Portsmouth - LeHavre
Newhaven - Dieppe

P & O Ferries
Dover - Calais

Norfolk Line
Dover - Dunkirk

Brittany Ferries
Portsmouth to Caen or St Malo
Poole to Cherbourg
Plymouth to Roscoff and Santander
Cork (Ireland) to Roscoff

Calais: 7h
St Malo: 4h30min
Caen: 5h
Dieppe: 6h
Cherbourg: 6h

(driving times approximate)