The symposium site is part of University campus, there is a possibility of cheap accomodation in dormitories, which are situated in walking distance to Biology Centre. City centre has also several nice hotels (below). You can commute from there via Public transportation which is pretty frequent or you can walk (approximately 25 min from Biology Centre to city centre).
Hotels and Guest houses
More accommodation possibilities can be found on Booking.
Most of the upper mentioned hotels also can be booked via Booking page.