Hungary has several World Heritage sites. These are:

Budapest, including the Banks of the Danube, the Buda Castle Quarter and Andrássy Avenue

Old Village of Hollókő and its Surroundings

Caves of Aggtelek Karst and Slovak Karst

Millenary Benedictine Abbey of Pannonhalma and its Natural Environment

Hortobágy National Park - the Puszta

Early Christian Necropolis of Pécs Sopianae

Fertő/Neusiedlersee Cultural Landscape

Tokaj Wine Region Historic Cultural Landscape

Other major tourist destination is Lake Balaton, with winehills, thermal spa in Hévíz around.

There are also some amazing things to see.

In mid-June the Tisza produces swarms of mayflies which are likened to flowers. Once decimated by pollution, the population is rebounding. They're famous for living only for 1-2 days.