Close upon and Close to

Close to and close upon are semantically related in nearly topic. In some cases you can use "Close to" instead an adverb phrase "Close upon", when it comes to topics like next to.

Close to adverb - (of quantities) imprecise but fairly close to correct.

Close upon and close to are semantically related in nearly topic. You can use "Close upon" instead an adverb phrase "Close to", if it concerns topics such as next to.