First, refer to different

1, in: somewhere.

2. Here it is.

Second, the emphasis is different.

1, at: followed by a locative noun.

2.at the: followed by a specific or unique place noun in the world.

Third, the use of quotations is different.

1, at: when at indicates position, it refers to a certain point in spatial position; A timetable refers to a certain moment.

2.at: English words, definite articles and adverbs, meaning "this; When "na" is used as an adverb, it means "more (used in comparative and superlative)".