This location is not accessible on disc 4
You can find Trabia Garden as soon as Balamb Garden is mobile, but you can't do anything here until you complete the events at Balamb. If Selphie is with you, she will run off (and if she isn't, she'll show up anyway).
The cemetery is to the right of the front gate, while everything else is to the left. There are a few goodies to find. You can get the Selphie Card from Selphie's friend, but not until they are done talking.
Talk to the student with the book in the classroom twice to get a hint: "Go south, 5 steps from Trabia Garden's gargoyle statue."
Once you reach the basketball court, you'll enter a revelatory flashback. You can walk around speaking to younger Squall, but you have to head for the beach to finish the sequence.
The cemetery is to the right of the front gate, while everything else is to the left. There are a few goodies to find. You can get the Selphie Card from Selphie's friend, but not until they are done talking.
Talk to the student with the book in the classroom twice to get a hint: "Go south, 5 steps from Trabia Garden's gargoyle statue."
Once you reach the basketball court, you'll enter a revelatory flashback. You can walk around speaking to younger Squall, but you have to head for the beach to finish the sequence.