Given you have just a day in Budapest, use the city's efficient and widely used public transport to save time and money. You can also choose to bike or walk between locations if you want to explore more of the city. A 24-hour travel card costs 1650 HUF per person and a shared bike service is also available.
If you have more time during your trip, you can also add a visit to the stunning Hungarian State Opera House or the Széchenyi Thermal Bath to relax and take a dip in Budapest's hot springs. For those with less time, consider skipping the Parliament Building or the Fisherman's Bastion as they can be time-consuming. Remember to carry cash as not all places accept card payments.