Suggestions for a day ride tomorrow( July 4th) ?

So I have an extended long weekend and so me and a buddy were gonna head out from about 10-5 just riding. We dont get out on alot of day trips like this, so out of all the roads where would you suggest we hit?
Im in Ajax and was thinking maybe headin over to the port hope backroads up to the 507 and then cut into the 503 towards southwood or the big chute or rousseau backroads just not sure how much we coould cover in the time we have?

Any suggestions woould be great!

Thanks!