515 The Genitive may denote the time or space within which something occurs, or to which it belongs:
Oὐ μαχεῖται δέκα ἡμερῶν he will not fight within ten days. AN. I. 7, 18. ἀεὶ τοῦ καθήκοντος χρόνου γίγνεσθαι occur always within the appropriate time. D. 4, 35. ἑπτακαίδεκα σταθμῶν τῶν ἐγγυτάτω ἐκ τῆς χώρᾱς οὐδὲν εἴχομεν λαμβάνειν within the sixteen nearest stages we could get nothing from the country. AN. II. 2, 11.
In prose only a few words of time, and still fewer of place, are freely so used, especially χρόνου, ἡμέρᾱς by day, νυκτός by night, ἑσπέρᾱς in the evening, χειμῶνος in winter, θέρους in summer.
Here also belong some adverbs and adverbial phrases of place in the genitive, as αὐτοῦ on the spot, ποῦ where? οὗ where (rel.): οὐκ ἔφασαν ἰέναι τοῦ πρόσω they refused to go forward. AN. I. 3, 1.