You can go by train to Debrecen.
Trains leave to Debrecen from the "Nyugati Palyaudvar", The West Main Railway Station.
You can buy a ticket for the Airport Minibus at the Transit Lounge, for 1500 HUF. It will take you to the Railway Station.
DO NOT TAKE TAXIS to travel to the Railway station!
At the Railway station buy a Full Rate train ticket to Debrecen for InterCity Train
Train Timetable can be found here.
Take the InterCity Train to Debrecen, as it is more convenient and faster than normal trains.
http://www.elvira.hu/Train Timetable can be found here.
Inter-city trains leave Budapest Nyugati-Station every 2 hours. Seat reservation is required on Inter-city trains. (13/9 EURO for first/second class single tickets, see railway information. The journey takes 2 hours and 47 minutes. Other trains are also available, but they are less comfortable.
Take public bus Nu93 from the airport to the metro line (Kobánya-Kispest), than the underground trains to Nyugati-Station using prepaid tickets (2 tickets ca. 1 EURO). (There are trains, although not Inter-city ones, directly from Kõbánya-Kispest to Debrecen. The Inter-city trains do not stop at Kobánya-Kispest.
One can take a tram (Nu1, the only one line in Debrecen) from the railway station to the Hotel Nagyerdõ (Pallagi út 5.)in Debrecen using prepaid ticket (110 HUF) or by taxi (about 1500 HUF, EURO 3-4). The same line goes to the University, where the central building (the former Kossuth University)
The weather in Debrecen in August is warm and dry. Temperatures range from 24ºC to 30ºC (75ºF to 86ºF). Occasional rain should be expected.
Airport Debrecen almost biggest airport in Hungary, it was a soviet military airport.Now it is a commercial, international, public airport with continuous custom and passport control service.MALEV, the Hungarian Airlines have a bus service to Debrecen too. These buses leave the Airport on every Tuesday, Friday and Sunday an 23:00. The Bus tickets can be obtained at the airport for 3900 HUF.
The Hungarian Airlines can be found at the website:
If you prefer to drive a car, Debrecen is accessible from Budapest via high way M3 to Polga'r (ca. 180 km) and road Nu 35 (55 km) to Debrecen.