1 day you need for local site seeing as mentioned in the link below.
What are the best places for a tourist to see in Gangtok?
- I plan on traveling across America but mainly through wilderness. What should I bring with me?
- If I ever go to Bolivia, what places should I visit?
- Ich bin auf der Suche nach einem reisenden Beruf, der Reisen in verschiedene Länder beinhaltet. Derzeit bin ich CA-Finalist. Wofür soll ich mich entscheiden?
- What are some solo travelling tips?
- Was ist der beste Weg, um eine Reise / ein Ziel / eine Reiseroute zu planen? Ich werde zum ersten Mal planen.
It will take one day to travel towards namchi that is south sikkim and to return.
One can visit west sikkim that is peling where one night stay is recommended to have morning view of kanchan jhunga.
Zuluk at east sikkim is a nice place with home stay.
Way to Tsamgo lake and Babamandir will depend upon road condition and usually take one day to visit from Gangtok.
Way to north sikkim to gurudongmar lake and zero point, which comprises of 3N/4D or 2N/3D also depend upon road condition.
From gangtok to darjeeling it will take few hours. One night stay at darjeeling to view sunrise at tiger hill and roam around near ghoom station, visit to zoological park at day time may complete your trip.