Lavrion is located on the southern part of Athens and its port serves ferries to few Cyclades islands, including Kea and Kythnos, and the Eastern-Aegean islands of Lemnos and Agios Efstratios.
From Athens Center:
The transfer from the Athens Center to Lavrio Port will normally take 1 hour the most, depending on the traffic.
From Piraeus:
The transfer from Piraeus to Lavrio Port will normally take 1 hour and 15 min the most, depending on the traffic.