Autoservizi Salemi runs regular buses between Marinella di Selinunte and Castelvetrano's train station (€1.50, 25 to 35 minutes, seven Monday to Saturday year-round, four Sunday July and August only), where you can make onward rail connections to Mazara, Marsala, and Trapani. For eastbound travellers, Lumia runs buses from Castelvetrano to Agrigento (€8.60, two hours, three Monday to Friday, two Saturday, one Sunday).
Car & Motorcycle
Coming from Palermo and other points north, take the Castelvetrano exit off the A29 and follow the signs (briefly east on the SS115, then south on the SS115dir). If you're driving from Agrigento, take the SS115 west for about 85km, then exit onto the SS115dir south. The turn-off for the ruins is clearly signposted, on the northwestern outskirts of the coastal town of Marinella di Selinunte.
There are 10 daily trains (four on Sunday) from Castelvetrano to Mazara del Vallo (€3.10, 20 minutes), Marsala (€4.30, 40 minutes) and Trapani (€6.20, 1¼ hours).