What's a good 3-day itinerary for Athens?

Day 1 stays on and around the Acropolis. The gates open at 8 AM, and at that hour the Pentelic marble still holds the night's coolness under your feet. Tour buses appear around 9:30. Give the Parthenon, completed around 438 BC, about 45 minutes on top, then descend the south slope to the Acropolis Museum by 10 AM. The ground-floor gallery has a glass floor over an excavated 5th-century neighborhood. Lunch at Thanasis on Monastiraki Square costs about 9 euros for a souvlaki plate, eaten at sidewalk tables where charcoal smoke drifts from the grill pit. Walk south into Plaka afterward for the Ancient Agora at 2 PM. The Temple of Hephaestus there is the best-preserved Doric temple in Greece, and it draws a fraction of the Acropolis crowds. Sunset drinks at A for Athens rooftop bar on Miaouli Street put you at Acropolis eye level, with a beer for about 7 euros.

Day 2 moves north to the National Archaeological Museum on Patission Street, a 15-minute walk from Omonia. Arrive at 9 AM. The Mycenaean gold hall on the first floor, with the Mask of Agamemnon from around 1500 BC, tends to hold people for 45 minutes on its own. Budget 2.5 hours total. Walk southeast through Exarchia for coffee at Taf on Emmanouil Benaki Street, where an espresso freddo costs about 4 euros. Rozalia on Valtetsiou Street is a courtyard taverna under a grapevine canopy. A plate of gemista, peppers and tomatoes stuffed with herbed rice, runs 10-12 euros. After lunch, head south through Kolonaki to the Lycabettus Hill funicular at Aristippou Street. The ride costs about 5 euros and takes 3 minutes. At 277 meters, Lycabettus gives you the widest view across Athens, from the Acropolis south to the Saronic Gulf. Come down on foot through the pine-shaded eastern path to reach Kolonaki Square by 6 PM.

Day 3 covers the western sites and the 1896 stadium. Start at Kerameikos, the ancient cemetery on Ermou Street, at 9 AM. Your combined Acropolis ticket from Day 1 covers entry. Kerameikos stays quiet even in June. Tall grass grows between 4th-century BC grave markers, and you might hear turtledoves in the cypress trees. Walk 10 minutes north to the Athens Central Market on Athinas Street. The meat hall smells of iron and dried oregano. The fish counters have the morning catch on crushed ice by 10 AM. For a late breakfast, find Diporto Agoras at the market's south end, a basement taverna with no sign and no printed menu. The cook serves chickpea stew or grilled fish for about 8 euros. Walk east from there to the Temple of Olympian Zeus, where 15 Corinthian columns still stand from the 2nd century AD. The Panathenaic Stadium sits 600 meters northeast. Workers rebuilt it entirely in marble for the first modern Olympics in 1896, and it still seats 50,000. Stop at Syntagma Square for the Evzones guard change on the hour. Finish at Mavro Provato in Pangrati for lamb chops at about 14 euros.

Athens in mid-June currently hits around 32°C by early afternoon, so the 8 AM starts on Days 1 and 3 are not suggestions. The combined Acropolis ticket costs 30 euros and covers 7 sites over 5 days. Buy it online to skip the ticket queue at the Acropolis entrance. The Athens Metro runs from 5:30 AM to midnight, with a 1.20-euro single ticket valid 90 minutes across metro, bus, and tram. Most of this itinerary is on foot, though. Total distance across the three days is about 25 kilometres. Flat shoes matter on the Acropolis. The path up is polished limestone, slippery even when dry. Plaka's streets are rough cobblestone. The Lycabettus descent is a dirt trail through pine forest.