You can find the venue as well as some additional interesting sites in the below map.
Some travel information can be found at the website of Jena Tourism.
Some rooms are reserved up to July 02, 2018 at the Hotel Schwarzer Bär (University Rate, 70€ per night, 10 minutes walk from the venue, (A) in the above map). Make sure to mention the reservation number 111755 and "resonances and Schrödinger operators", when calling there.
The following hotels are also close to the venue and have prices ranging between 50€ and 70€ per night.