The accommodations here offered are some of the options with the best quality/price ratio in town. They are all within walking distance (max 15 min) from the main conference venue (Barriola Centre) and the rest of locations where activities related with the conference will be held. Note that the accommodations must be booked through their own web systems (with reduced prices using the promotional code provided when registering to the conference). Promotional coupons will be valid until May 31st.
If you want to book accommodation somewhere else, bear in mind that the conference does not provide promotional codes for any other Hotel and that Donostia is an expensive city, more so during summertime.