Suggestions for Tuesday evening:
(1) Take tramway no. 1 to direction Durlach and exit at the stop Durlach Schlossplatz.
The tram takes 20 minutes. With a short walk you can explore the historical Durlach, which was the capital of the country Baden-Durlach before Karlsruhe was founded and has a medieval layout, with circular streets around the church. See Durlach Castle at the tram stop and then walk back in the direction which you came from to see the old city hall next to the church. Walk south to see the tower Basler Tor and remnants from the city wall. You may also want to walk on the Turmberg hill with its ruin of an old fortress. There are many restaurants in Durlach, e.g. La Dolce Vita, Sol y Luna or La Violetta.
(2) Take tramway no. S1 or S11 to direction Bad Herrenalb or Ittersbach and exit at stop Ettlingen Erbprinz/Schloss. The tram takes 30 minutes. Visit the baroque castle and walk northeast to the historical city hall (Rathaus). Cross the small river to enter the medieval old town with its small alleys and the city wall with the old tower Lauerturm. You find plenty of restaurants.
(3) Walk from the conference site to Kaiserstraße 12 over the Campus. At the Ehrenhof (East side) there is a memorial site for the discovery of electromagnetic waves by Heinrich Hertz. Cross Kaiserstraße and go through Fasanenstraße to enter the Dörfle, Karlsruhe's old town. After taking a walk around there take Zähringerstraße to Marktplatz with its classicistic city hall and Marktkirche church. Walk to the castle and then go along the line of the west wing to see Germany's Constitutional Court, with nice modern post-war architecture. You may take Stephanienstraße to see old buildings, including the mint of Baden (Staatliche Münze), where you turn left into Karlstraße, with the Prinz-Max-Palais on the right side and then the old post office at Europaplatz. Nearby at Ludwigplatz there is nightlife with lots of restaurants.
Suggestions for Sunday or Wednesday afternoon:
(1) Take a tram to the station and then a regional train to Baden-Baden. The trip takes about 45 minutes, but you need to take a bus to reach the historical center of Baden-Baden. See the Casino where Dostojevski gambled and many old 19th-century hotels. There are excavations from Roman time near the Caracalla spa. Take the Merkurbahn up to the Merkur hill to see remnants of a Roman site where god Mercurius was worshipped. There is a restaurant on the hill top and many good (and expensive) restaurants downtown. I recommend La Casserole, Stromboli, and Rizzi.
(2) Take a tram to the station and then a regional train to Landau. The trip takes around 1 hour. Landau is a baroque city (with a rectangular street pattern) which is due to French king Louis XIV.
(3) Take a tram to the station and then a regional train to Neustadt (Weinstraße), a medieval city. The trip takes about 75 minutes and can be combined with (2).
(4) Take tramway no. S1 or S11 to Bad Herrenalb, which takes about 1 hour. The train trip takes you through the Black Forest, in Bad Herrenalb (a spa town) you may visit the typical Tudor-style houses of the area and take a short hike through the forest, e.g. to the Falkenfelsen lookout.
