What is the meaning of "grand large"

Question

I encountered the expression

des ballades au grand large.

What does it mean? What is its etymology?

Answer 1

« Le large » a un sens qui signifie La haute mer, par opposition à la côte.

« Le grand large » est une emphase de la haute mer.

Answer 2

@Toto's answer is fine. As a side remark, a little of googling gave:

Décidément attiré par le grand large, le jeune Chirac embarque comme marin sur un cargo, avant que son père ne le ramène dans le droit chemin..

i.e.

Decidedly attracted by the open sea, the young Chirac embarks as a sailor on a freighter, before his father brings him back on the right track.

There is also a nice article about open sea, grand large, haute mer available for download here: https://journals.openedition.org/bagf/2053

By the way, I found also that grand large could have another sense in the past (rare nevertheless)

Vieux et rare. [En parlant d'un tissu] Au grand large. En grande largeur. Ayez la bonté de m'acheter (...) une aune de lévantine noire au grand large : c'est pour faire un tablier sans couture (Sand, Corresp., t. 1, 1829, p. 75).

according to https://www.cnrtl.fr/definition/large