A day in Arcachon from Bordeaux
 

During a stay in Bordeaux in April, my group of four would like to visit Arcachon. We are interested in great food and beautiful scenery; not big on hiking, but we like bicycling. Is it possible to enjoy a day trip by train? Do you recommend any tour companies? I don't think we should attempt to drive a car!

Arcachon area s worth a visit. We had some of the best oysters ever in l'Herbe. Here's the view we had while having them:

https://flic.kr/p/a73KYk
The dunes are also of interest:

https://flic.kr/p/a76FBC
But I honestly can't imagine seeing the area without a car.

There is a bike path between them. Cycling is a great way to tour the area.
There is also a major eurovelo route down the Atlantic coast of France which circles the bay and makes a full visit by bike very easy. Lots of bike hire about.