if you are wanting to check bags but still show up initially at the International terminal, because it's close to parking, than you can take the ground shuttle between the International terminal and and another terminal pre-security. Explanation is below...


ATL Ground Transportation Pre-Security (Landside)
You can travel between the Domestic and International Terminals (without passing through security) by taking the airport shuttle service.

If arriving from the MARTA station or from other entry points on the western side of the Domestic Terminal, you need to enter through the W2 door into the South Terminal baggage claim area. From here, you can follow signs to Ground Transportation where you can pick up the shuttle bus to go to the International Terminal.

From the International Terminal, you can pick up the shuttle bus from the northern area of the terminal through doors A1, A2, or A3. The shuttle journey between terminals takes around 12 minutes.