Sydney

 You don't need any stars to unlock this city. 

You get 75 coins for a city question. 

Berlin

 You need 35 stars to unlock this city. 

You get 55 coins for a city question. 

City Sights of Berlin: 

The Berlin Wall (5 tickets)

Halloween event 2021

These are the jobs that I had to do and the rewards that I received. Don't know if it's different for you? 

Kathmandu city questions

These are not the City Sights (for the City Sights of Kathmandu, go here), but just the questions that pop up in the streets. As they are so hard to remember to me (even to read those long words in the questions took most of the 20 seconds), I decided to make a list (far from complete). 

Update: I just heard from somebody who started this year (2021), that she had none of these questions, only general questions about the world. About flags and pasta, not difficult at all. It's different for some people. 

Brasília - City Sights

Monumento JK President Kubitschek Memoria

The Monumento JK is a mausoleum and presidential memorial dedicated to the 21st president of Brazil, Juscelino Kubitschek. JK was medical doctor before he going (?) into politics. He was mayor of Belo Horizonte and he run for president under the slogan “Fifty Years Progress in Five”. Kubitschek died in a car crash in 1976. His memorial, designed by the architect Oscar Niemeyer, opened to the public in 1981. The Monumento JK is located in the Eixo Monumental road, and its main column is 28 meters high. The stained glass inside the Memorial was designed by Marianne Peretti. The memorial contains Kubitschek’s collection of 3000 books and outside you can see his car, a For Galaxie LTD. Also there is a bronze statue of him with Sarah Kubitschek. Wagner Moura played young Kubitschek in a film in 2006. Also, did you know that in Kubitschek Plaza Hotel they serve JK’s pudding secret recipe?

Jakarta - City Sights

National Monument

The national monument is a 132 m obelisk in the centre of Merdeka square in central Jakarta. The National Monument or Monumen Nasional – Monas for short – symbolizes the struggles during the Indonesian National Revolution between the years 1945 and 1949. The construction of the monument started in 1961 and it was first open to the public in 1975. The monument encapsulates the philosophy of lingam and yoni, the harmony between the feminine and masculine energy of Shakti and Shiva. It also resembles the bloom of the amorphophallus titanum or titan arum, an endemic flower of Sumatra. In the outer yard of the monument there are reliefs that depict instances of the Indonesian history.