Day 1 — Sofia: ancient Serdica, the rotunda, and mineral springs
🚇 If you are flying into Sofia, the most convenient budget-friendly start to the route is the metro from the airport. Sofia Airport station is at Terminal 2; it is easy to ride line M4 toward the city center. To the Serdika hub, travelers usually allow about 30–35 minutes including waiting time for the train and exiting the station, and from there you can walk to almost all the main sights of the day. This is one of those rare European capital routes where the airport line brings the traveler almost naturally straight to ancient ruins.
🚶 Start your introduction to Sofia with the ancient Serdica complex around Serdika station and Independence Square. Here the modern city literally stands on top of the Roman one: under glass and along open sections you can see fragments of streets, residential quarters, early Christian buildings, and fortification elements of the former city of Ulpia Serdica. This is not a museum in isolation, but a living urban fabric where the metro, administrative buildings, and ancient stones coexist in a single frame. What is especially impressive is the feeling of layered history: you go down through a passageway as if entering an ordinary transport hub, and find yourself in a space where it is easy to imagine the noise of a Roman provincial capital, trade, baths, church processions, and the continuous history of a city by hot springs.
🚶 Then walk to the Rotunda of Saint George, the oldest preserved building in Sofia, hidden in an inner courtyard among later administrative and hotel blocks. This 4th-century red-brick rotunda makes a strong impression precisely through the contrast in scale: from the outside it feels intimate, almost quiet, but in historical importance it is one of the key places in the Bulgarian capital. Here you can sense the transition from the ancient world to the Christian one, from an imperial quarter to a medieval city. Inside and around it, you feel especially clearly that Sofia does not so much display ruins to tourists as continue living on top of them, without hiding its own antiquity.
🚶 After that, head to the former Central Mineral Bath, which today houses the Regional History Museum Sofia, while the famous mineral springs flow in the square nearby. This is a very important place for understanding the character of the city: Serdica developed thanks to the hot springs, and Sofia still retains its reputation as a city of water, steam, and healing baths. The former bath building itself is bright and decorative, with architecture typical of the early 20th century, and near the fountains you can see locals with bottles and canisters. This is a particularly pleasant point in the route to slow down: visit the museum, then step out to the water, sit in the square, watch the rhythm of ordinary city life, and feel that the mineral theme in Sofia is not a tourist backdrop but a genuine part of everyday life.
🚶 To end the day, it makes sense to walk through the Central Market Hall and the neighboring streets of the old center. Even if food is not your main focus, the market helps you see a more grounded, everyday Sofia: less ceremonial, more urban temperament. Within walking distance are also Banya Bashi, the Sofia Synagogue, and the streets around the Women’s Market, so the first day becomes very rich in cultural layers: Roman Serdica, Orthodox and early Christian history, Ottoman heritage, market life, mineral water, and everyday Sofia. For this route, with a museum stop and some rest, it is convenient to allow almost a full day, around 7–9 hours without rushing.