More info about interest points:
1) Sibelius Monument - https://www.myhelsinki.fi/en/see-and-...
2) Temppeliaukio Church - https://www.myhelsinki.fi/en/see-and-...
3) Central railway station - https://www.myhelsinki.fi/en/see-and-...
4) Uspenski Cathedral - https://www.myhelsinki.fi/en/see-and-...
5) Helsingin tuomiokirkko - https://www.myhelsinki.fi/fi/n%C3%A4e...