Although it's situated in south Dalmatia, area of Dubrovnik on the far south of Croatia - except lack of highway, traffic connections of Peljesac are completely satisfying. Therefor, depending of plannesd route of your voyage, consider one of the following options:

Considering that you're probably arriving from north, you may decide to take different paths to Ploce (area of Neretva valley), where you can decide would you like to take a car ferry to Trpanj, or take the coastal path trough Neum (BiH) and Ston.

Usual paths from Zagreb to Ploce are:
Zagreb - Karlovac - Plitvice - Gracac - Knin - Sinj - Split - Makarska - Ploce
or not so often:
Zagreb - Karlovac - Plitvice - Gracac - Knin - Sinj - Trilj - Cista Provo - Sestanovac - Dubci - Makarska - Ploce

Both routes are acceptable, but some guests from eastern European countries may find more acceptable path trough Bosnia and Hercegovina towards Neretva valley - (Opuzen, Ploce).

In town Ploce you may decide if you are tired enough or not in the mood to drive any more, and shorten your way by the sea route - taking the car ferry to Trpanj. Otherwise you may take coastal road trough Neum (BiH) to Ston and further on Peljesac.

You can also take one of following boat lines, in case that boat can take your car.

Fast coastal line connects Rijeka, Split, Hvar, Korcula and Dubrovnik. Korcula is well connected with Orebic (Peljesac) with frequent car ferry and connected with Orebic and Viganj with passenger boat.

The closest airports are in Dubrovnik and Split. Both cities are linked with both boat and bus lines to Peljesac.