Klabat
Klabat is a stratovolcano (a volcano composed of both lava flows and pyroclastic material) and fumarolic (a volcano with a vent or opening through which issue steam, hydrogen sulfide, or other gases; the craters of many dormant volcanoes contain active fumaroles). Klabat has been inactive for a long time. It is the highest mountain in North Sulawesi. Good for climbing and camping.
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Lokon
Lokon is a stratovolcano located near the small town Tomohon, a town in the Minahasa regency, about 25 km from Manado city. It has had 21 eruptions in historic times. Lokon and its twin volcano, Empung, rise about 800 m above the plain of Tondano. Lokon is higher than Empung, and the summits are only 2.2 km apart. The two volcanoes are among the most active volcanoes of Sulawesi. There is no crater at the summit but only a flat area. Empung crater, which is younger than Lokon, has a width of  400 m and 150 m deep. There is an active crater, Tompuluan, which is located at the saddle of these two peaks. This Tompuluan crater is better known as the Lokon crater, and is 250 m long and 150 m wide. The easiest way to reach the summit is through Kakaskasen, in a one hour walk. The Volcanic Observatory is located at Kakaskasen, a suburb of Tomohon. 

Mahawu
Mahawu is a stratovolcano located near the small town of Tomohon. Mahawu is a favorite place for climbing activity in Great Minahasa. The easiest way to reach the summit is from Kakaskasen. The crater wall can be reached in about one hour on foot. 

Soputan
The small conical volcano of Soputan on the southern rim of the Quaternary Tondano caldera is one of Sulawesi's most active volcanoes. This young largely unvegetated volcano is located SW of Sempu volcano and evolved at the southern end of a SSW-NNE trending line of vents. In earlier times the locus of eruptions has included both the summit crater and Aiseput, a prominent NE flank vent that formed in 1906 and was the source of intermittent major lava flows until 1924. Eruptions of Soputan: spectacular eruption in May 2000. Also in 1991-93, 1991, 1989, 1985, 1984, 1982, 1973, 1971, 1970, 1968, 1966-67, 1953, 1947, 1923-24, 1917, 1915, 1913, 1911-12, 1910, 1908-09, 1907, 1906, 1901, 1890, 1845, 1833, 1819, 1785.

Tangkoko
Tangkoko is a stratovolcano rising 1149 m above sea level.  It has a deep crater as well as a parasite cone named G.Batu Angus Baru. Tangkoko is located at 1° 31' N and 125° 11.5' E while Batu Angus Baru at 1° 30.5' N and 125° 13' E. Tangkoko and its volcano neighbor named Dua Saudara have a simple morphology. They are divided by a raised path. At the foot of this raised path is the source of both Batu Putih and Air Prang rivers. Tangkoko has an elliptical shape. Tangkoko's crater is 2 km x 1 km in diameter and is 200 m deep.  At the southern flank of Tangkoko, 2 km away, the lava dome of Batu Angus Baru is found. Historical records of Tangkoko show that more eruptions have occurred at Batu Angus Baru; no inhabitants have been reported killed. However, future eruptions may cause many victims as the area around the volcano is now densely populated.

Sources:
1.  Regional Office of Public Work, North Sulawesi
2.  Smithsonian Institution's Preliminary Notices of Volcanic Activity
3. Volcanological Survey of Indonesia
4. Vulcano live