How to get there?
If you are not already in Indonesia, the best way to get to Manado is via Singapore. Currently there are 3 to 5 direct flights a week from Singapore to Manado with Silk Air.
Since Silk Air is a daughter from Singapore Airlines, it is best to get to Singapore with Singapore Airlines. The ticket to Manado is much cheaper than. From almost every western and asian country there are daily flights to Singapore. But you can of course also go to Singapore with other airlines.
Another way to get here is by flying via Jakarta. Many countries and airlines fly directly to Jakarta and from there you can fly with domestic airlines like Garuda or Lion Air, to Manado. This can be direct but is often also with 1 or 2 stops. Another good option is to fly via Denpasar on Bali. Internationally there are many (cheap) flights going daily to Denpasar. From there it is easy to book a domestic flight to Manado. Either direct or via Makasar (Ujung Pandang).
A great web site to find and book domestic tickets is: www.ticketindonesia.info
Free Visa on Arrival in Manado.
There are a number of countries that can get a free visa on arrival in Manado for the purpose of tourism for 30 days. Currently these countries are:
People’s Republic of China, Russia, South Korea, Japan, United States of America, Canada, New Zealand, Mexico, England, Germany, France, Netherlands, Italy, Spain, Switzerland, Belgium, Sweden, Austria, Denmark, Norway, Finland , Poland, Hungary, Czech Republic, Qatar, UAE, Kuwait, Bahrain, Oman and South Africa.
If you are a citizen from a country not in this list you have to pay 35,- US$ to get a visa on arrival or possibly have to apply at the Indonesian embassy in your country. If you want to stay longer then 30 days, you have to apply at the embassy as well.