Thanks, pookie!
Also:

Hungary: serious country (2015) put up in record time.
In 2015, Hungary built a border barrier on its border with Serbia and Croatia. The fence was constructed during the European migrant crisis (see timeline), with the aim to ensure border security by preventing illegal immigrants from entering, and enabling the option to enter through official checkpoints and claim asylum in Hungary in accordance with international and European law.[4] The number of illegal entries to Hungary declined greatly after the barrier was finished as it effectively abolished the entry to Hungary.[5]
The fence was completed between Serbia and Hungary between June and September of 2015. Other sections of fence were put up on Croatian and Slovene borders. Illegal immigrant flow decreased from a peak of 138,396 in Sept 2015 to 152 in the following September.
Source (and considerably more information and images):
https://en.wikipedia.org/wiki/Hungarian_border_barrier