I don’t recommend to walk alone in the dark

Sempre aperta...

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There are quite a lot of stairs...from bottom to top it's about ten minutes or a quarter of one hour if you don't stop for a break and you go fast... going slower it's about 20 minutes- half an hour...

si puo arrivare in macchina solo fino a 300-400 mt dalla statua poi bisogna camminare ma non è così difficoltoso.

I hope I'm right- it's opening hours are 9.30-7.30 but not sure about the price. Couple of years ago it was 500Ft (HUF)

I believe you can drive up, but it might be restricted to taxis and public use vehicles. Ask at your hotel, because it is really quite a hike up. At the top, they do sell bottled water etc.

Yes it is worth it. Everything in Budapest is worth it. Some of our best pics are from up there. If you are fit enough you will be able to climb the steps, just take your time. Lovely views all the way. We are both nearly 60 and walked everywhere in Budapest, we did not want to miss anything. The only time we used transport was too and from the airport. Budapest is fantastic. We would go back. Enjoy!

Not sure exactly a guess over 200 metres. I paced it walking up on the footpaths and it took what seamed like an hour, but I did take in the views on the way. Get the Berlitz guide book to Budapest as it gives tons of information.