How to get to Spetses
Spetses has no airport and never will, so everyone arrives by boat. The good news is that there are two quite different ways to do it, and which one suits you depends less on budget than on whether you are coming straight from Athens or travelling through the Peloponnese first. The direct route is the fast boat down the Saronic from Piraeus, which is what most visitors take and what most itineraries assume. The alternative is to drive round through the Argolid to the coast facing the island and make the short hop across, which is quicker overall if you are already on the mainland and want to see Nafplio or Epidaurus on the way. Sailings run year-round and thicken considerably in summer. In high season, and especially for Friday evening and Sunday return crossings, book ahead rather than turning up at the quay.
By ferry
The main link is the fast catamaran and hydrofoil service from Piraeus, leaving from the Saronic gates at the eastern end of the port. Allow around two hours, a little more on the sailings that call at Hydra and the other islands on the way down, a little less on the more direct runs. There are several departures a day through the summer and a reduced service in winter. Book online in advance in July and August, because these boats do sell out. The crossing itself is usually easy. The Saronic is sheltered, and the meltemi that batters the Cyclades in midsummer barely registers here, so this is a gentle introduction if you are a poor sailor. The far shorter option is the crossing from Kosta, on the Peloponnese coast directly opposite. This is a matter of minutes rather than hours: a small car ferry runs across through the day, and a fleet of water taxis will make the trip on demand at any hour, which is the usual choice for anyone arriving late or in a small group. Leave your car in the parking at Kosta. Vehicles belonging to visitors are not permitted on Spetses, so the car stays on the mainland regardless.
By plane
There is no airport on Spetses, and given the size of the island there is nowhere sensible to put one. Athens International (ATH) is the gateway. From there you either continue to Piraeus for the fast boat, using the metro or the express bus into the port, or pick up a hire car and drive round through the Argolid to Kosta, which takes something over two hours and lets you break the journey at Epidaurus or Nafplio. Allow half a day either way from touchdown to the harbour at Dapia.
Other options
Once you are here, the island does the rest. Visitors cannot bring cars, and the town centre is closed to general traffic, tightest through the summer, so the practical options are your own feet, two wheels, a horse and a boat. Walking covers the town comfortably. Mopeds and scooters are widely hired and are what most people use to reach the far side of the island, and bicycles work well on the coastal loop road, which is flat and shaded for much of its length. The horse-drawn carriages on the quay at Dapia are a genuine survival rather than a photo opportunity, though they are slow and not cheap. For the beaches, water taxis run from the harbour and are usually the fastest way to the coves. Taxis, delivery vans and service vehicles do exist, so expect some engine noise.