Why not use sur?

Question

Bonjour, 
Hello I was wondering for one of your example sentences you use le  not sur why not sur?
On aime aller se  balader  le weekend.
Thanks
Nicole

Accepted Answer

Bonjour Nicole,
As mentioned in the lesson, in French to say :
- on + days of the week = 'le' + jour de la semaine
Le lundi, je fais la lessive = On Mondays, I do the laundry
Attention : specific context -> On + day 
Mardi, je fais les courses = On Tuesday, I go food shopping
 
- at the weekend = 'le week-end'
Le week-end, je tricote = at the weekend, I knit
Attention: This weekend = ce week-end
 
I hope this is helpful.
Bonne journée !

Answer

You never use the preposition sur when specifying a date in French. It would be a literal translation of the English "on" which simply doesn't work in French.