Increased activity of the Turrialba volcano has recently caused airport closures and this could happen again at any time. See Natural disasters
Around 54,000 British nationals visited Costa Rica in 2014. Most visits are trouble-free, but incidents of violent crime against tourists have increased. See Crime
There is a low threat from terrorism. See terrorism
Since early 2013 there has been a sharp increase in cases of dengue and other mosquito-borne diseases. See Health
You should take out comprehensive travel and medical insurance before you travel.