As is usually the case following a terrorist incident, hotels in the targeted city suffer and Brussels is no different.
Following the March 2016 attacks on the city's airport and metro, visitors quickly changed their plans and the city's hotel sector went into decline.
However new research from hotel analysts STR shows that the Belgian capital is now on the road to recovery.
Our chart this week shows occupancy levels started to bounce back in November after months of decline and they have now grown for five consecutive months.
November 2016 occupancy levels were 10.2% higher than the previous year. January and February of this year were relatively flat but March, a year on from the attacks, showed an increase in occupancy of 19.4%.
Despite this, STR says that the city is not entirely back to normal. March 2017's absolute occupancy level was 69.0%, down from 71.9% two years ago.
So what is driving these figures? Leisure traffic clearly takes a hit in the aftermath of such events but group business is driving the return to heath for the city's hotel sector. Group bookings were up 40.4% year on year.
The city regularly tops the world rankings for international association congresses and event organisers appear to be coming back to the city.
Thomas Emanuel, STR's director of business development, says, "Our latest forecast suggests that Brussels hotels should continue performance recovery throughout the remainder of the year. Following a 16% decline in demand in 2016, we should see an uplift of 15% for 2017 as both tourism and business travel continues to increase. This is assuming, however, that the market does not experience any further security incidents."
You would not expect transient business travel to be affected as much — when business needs doing, people travel to carry it out. Yet even here, companies are recognising that travel risks need to be assessed before signing off on a trip to somewhere as traditionally 'safe' as Brussels.