Hello, I think hour to hour and a half is more than enough for a quality visit at the observatory. I would recommend to first see the observatory (the Greenwich meridian), and then carry onto something else. As for the parking, not too sure as I don’t drive and we used the public transport. Best wishes and lots of fun

It's best to check with Observatory, as you will appreciate this is only seen in twilight dark, not during a daylight visit

Il biglietto può essere tranquillamente acquistato sul posto, non c’è fila

the Greenwich line is free to see

Salve, da fuori è possibile vederli entrambi ovviamente non vedi la linea a terra con tutti i riferimenti e comunque tutto l'osservatorio merita la visita ed il prezzo del biglietto . Io ho fatto un biglietto cumulativo che prevedeva visita al Cutty Sark e l'Osservatorio , fatto tutto on line ricevuti a casa i biglietti risparmiato il 10% . saluti

Esp Weekends before or after lunch. Opening hours 10.00-17.00. I recommend to be there at 10 am or during lunch or at 4pm. Best time might be 10am

Yes, is outside.

I would say allow an hour or two at least; maybe more if you wanted to spend some time at the planetarium part; we got there rather late in the day and had to rush through , but the good part of that is it was not crowded that time of day..... it is quite a hike to the top of the hill where the observatory is located ... in a pretty park; lovely views of London from up there... but it did take a bit of time getting up there and we were trying to rush to get there in time so I was quite out of breath!!!