On the return of the Peloponnesians from Attica the Spartans themselves and the nearest of the Perioeci at once set out for Pylos, the other Lacedaemonians following more slowly as they had just come in from another campaign.
Word was also sent round Peloponnese to come up as quickly as possible to Pylos; while the sixty Peloponnesian ships were sent for from Corcyra and being dragged by their crews across the isthmus of Leucas, passed unperceived by the Athenian squadron at Zacynthus, and reached Pylos, where the land forces had arrived before them.
Before the Peloponnesian fleet sailed in, Demosthenes found time to send out unobserved two ships to inform Eurymedon and the Athenians on board the fleet at Zacynthus of the danger of Pylos and to summon them to his assistance.
While the ships hastened on their voyage in obedience to the orders of Demosthenes, the Lacedaemonians prepared to assault the fort by land and sea, hoping to capture with ease a work constructed in haste, and held by a feeble garrison.
Meanwhile, as they expected the Athenian ships to arrive from Zacynthus, they intended, if they failed to take the place before, to block up the entrance of the harbour to prevent their being able to anchor inside it.
For the island of Sphacteria, stretching along in a line close in front of the harbour, at once makes it safe and narrows its entrances, leaving a passage for two ships on the side nearest Pylos and the Athenian fortifications, and for eight or nine on that next the rest of the mainland: for the rest, the island was entirely covered with wood, and without paths through not being inhabited, and about one mile and five furlongs in length.
The inlets the Lacedaemonians meant to close with a line of ships placed close together, with their prows turned towards the sea, and, meanwhile, fearing that the enemy might make use of the island to operate against them, carried over some heavy infantry thither, stationing others along the coast.
By this means the island and the continent would be alike hostile to the Athenians, as they would be unable to land on either; and the shore of Pylos itself outside the inlet towards the open sea having no harbour, and, therefore, presenting no point which they could use as a base to relieve their countrymen, they, the Lacedaemonians, without sea-fight or risk would in all probability become masters of the place, occupied, as it had been on the spur of the moment, and unfurnished with provisions.
This being determined, they carried over to the island the heavy infantry, drafted by lot from all the companies.
Some others had crossed over before in relief parties, but these last who were left there were four hundred and twenty in number, with their Helot attendants, commanded by Epitadas, son of Molobrus.