By train

Take the ICE, IC, EC or S-Bahn to Heidelberg Central Station; from there you can reach MPIA by public transport or by taxi.

The website of Deutsche Bahn offers a searchable timetable; if you put "Heidelberg, Max-Planck-Institut für Astronomie" as your destination, the resulting itinerary will include public transportation from Heidelberg main station to MPIA. You might need to pay an extra charge if you buy your ticket on the train or if you take an especially fast train (ICE or IC) with a supplementary charge not included in your original ticket.

Downtown Heidelberg ↦ MPIA

• Bus 39: Bismarckplatz – MPIA (Königstuhl, Sternwarte; travel time ca. 40 min)
  get off at Sternwarte, walk to MPIA (10 min)
  Departure: Bus leaves Bismarckplatz on the hour 6:00 - 19:00 h (all days), on workdays also at 8:43 am.
• Bus 30 (Science Bus): Altstadt – MPIA (Königstuhl, ca. 15 min) – working days only
  Science Bus 30 is a direct bus from Altstadt, Universitätsplatz to MPIA
  Departure times: Workdays only 7:27 am to 7:27 pm hourly, except 1:27 pm
• Ruftaxi 1007: replaces the bus after 8 pm
  Goes directly from Bismarckplatz to MPIA, no stops (except Sternwarte) in between.
  Important: you need to call in a reservation > 1/2 h in advance under 0621 1077077!
  Departure times (Bismarckplatz): 8:10 pm, 9:10 pm, 10:10 pm, 11:10 pm, 12:10 am
• Funicular: From Kornmarkt (near City Hall) to Königstuhl (15 min. on foot to MPIA)
  Departure times:
  every 10 minutes from 9:00 am till 8:20 pm (summer)
  every 10 minutes from 9:00 am till 5:10 pm (winter)

MPIA ↦ downtown Heidelberg

• Bus 39: walk from MPIA to bus stop Sternwarte (7-10 min)
  Departure times: 6:32 am to 7:32 pm, hourly
• Bus 30 (science bus): leaves in front of MPIA main entrance
  Departure times: Workdays only 7:48 am to 7:48 pm (except 1:48 pm)
  Science Bus 30 is a direct bus from MPIA to Altstadt, Universitätsplatz
• Ruftaxi 1007: replaces the bus after 8 pm
  Goes directly from MPIA to Bismarckplatz, no stops (except Sternwarte) in between.
  Important: you need to call in a reservation > 1/2 h in advance under 0621 1077077!
  Departure times (in front of MPIA main gate): 8:26 pm, 9:26 pm, 10:26 pm, 11:26 pm, 12:26 am
• Funicular: From Königstuhl (15 min. on foot from MPIA) to Kornmarkt (near City Hall)
  Departure times:
  every 20 minutes from 9:08 am till 8:08 pm (summer)
  every 20 minutes from 9:08 am till 5:28 pm (winter)

General information on public transport

Tickets can be bought at ticket machines, which are located at most stops (although not up on Königstuhl); Bus tickets can be purchased from the driver. Tram tickets need to buyed beforehand. Bergbahn tickets can be purchased directly at the Bergbahn stations.

Rhein-Neckar-Verkehr GmbH (RNV) is a member of the Rhein-Neckar transport association (VRN).

You can speak personally to a service agent at the RNV Service Centre (RNV-Kundenzentrum) across the main station at Kurfürstenanlage 62. Heidelberg main station is about 8 km from MPIA.