Heidelberg is a year-round city, and each season gives you a different version of it. The castle and Old Town are open throughout the year, but some things are seasonal, including boat trips, outdoor dining, the Christmas market and the number of palace tours at Schwetzingen. Here is what to expect in each season so that you can choose the one that suits you.
Spring
From March, the hillsides turn green and the gardens on the Philosophers' Walk start to bloom, and the days lengthen enough for late walks. April and May are among the most pleasant months for walking, with comfortable temperatures and fewer crowds than summer. Asparagus appears on restaurant menus in spring, and terraces start to fill. Showers are common, so carry a light waterproof, and use the Kurpfälzisches Museum or the Church of the Holy Spirit as a shelter.
Summer
Summer is the busiest and warmest season, and the Old Town is lively until late. Scheduled public boat sailings on the Neckar are a seasonal service that runs in the warmer months, so this is the time to plan a river trip, while private boat trips can run through much of the year. The castle is the busiest in the middle of the day, so go early or late. The castle courtyard also hosts summer open-air performances, and the castle is illuminated with fireworks on a few evenings each summer. Check the tourist office for dates, because they change every year. Temperatures can be hot, so carry water for the climb and wear a hat on the Great Terrace, which has little shade.
Autumn
September and October bring clear light, warm sandstone and changing leaves on the forested hillsides, which makes the view from the Philosophers' Walk and the Königstuhl especially beautiful. Crowds thin out after the summer holidays, and the trade-fair calendar can push up hotel prices on some weekdays. By early November, the funicular moves to a shorter winter timetable and the days draw in, so plan outdoor sights for the middle of the day.
Winter and the Christmas market
Winter is cold, often grey, and sometimes frosty, but it has a charm of its own. The Christmas market spreads over six Old Town squares from late November to just before Christmas, with wooden huts around the Hercules Fountain, a winter woodland on the Kornmarkt, a historic carousel and an ice rink at the Karlsplatz. The market is a seasonal event, so nothing is open before it starts, and weekends are crowded. Hotels in the Old Town sell out early for market weekends, so book well in advance. After the market ends, January and February are quiet and good value, but palace tours at Schwetzingen are fewer, and mostly in German, and the courtyards and cellars at the castle are cold.
What stays open all year
The castle courtyard, terrace and cellar are open every day through the year, the Old Town and the Hauptstraße are always walkable, and the museums keep their regular schedules, with a weekly closing day at some of them. The Bergbahn funicular runs on a summer or winter timetable, so check the hours for the day, especially for the Königstuhl summit.
What to pack
In every season, bring shoes with good grip for cobbles and hillside paths. In winter, add layers, gloves and a hat, because much of the visit is outdoors and the castle cellar is cold. In summer, bring sun protection and a refillable bottle, and in spring and autumn, a light waterproof.
So when should you go?
For the best balance of weather, light and crowds, aim for late April to June, or September to early October. For atmosphere and festive lights, choose the Christmas market weeks, accepting crowds and higher hotel prices. For the best prices and the quietest streets, go in January or February and plan around the cold. Whenever you come, give yourself at least two days, and see the first-time guide for how to organise them.
