The Prince. Chapter XIV. Paragraph 4.
“…and learns something of the nature of localities, and gets to find out how the mountains rise, how the valleys open out, how the plains lie, and to understand the nature of rivers and marshes, and in all this to take the greatest care. Which knowledge is useful in two ways.”
“Firstly, he learns to know his country, and is better able to undertake its defence;”
(1) For the immediate benefit of learning geography
“afterwards, by means of the knowledge and observation of that locality, he understands with ease any other which it may be necessary for him to study hereafter; because the hills, valleys, and plains, and rivers and marshes that are, for instance, in Tuscany, have a certain resemblance to those of other countries, so that with a knowledge of the aspect of one country one can easily arrive at a knowledge of others. And the prince that lacks this skill lacks the essential which it is desirable that a captain should possess, for it teaches him to surprise his enemy, to select quarters, to lead armies, to array the battle, to besiege towns to advantage.”
(2) For the recurring benefit in later situations
More abstractly, there is a benefit to learning about something which is ever-present and applicable everywhere.