The most important tourism fair on the Portuguese calendar had the first three days of the event dedicated to professionals. During the weekend, the BTL opens its doors to the general public. The 29th BTL centres on Nature Tourism, and will also see exhibitors from as far afield as Argentina, Zimbabwe, Taiwan and South Africa marking a presence at the event. Organisers are expecting visitor numbers to reach at least the 75,000 who walked through the turnstiles in 2016.