At their best in December
The months each trek's sources call the best.

Kalsubaiकळसूबाई
Western Ghats · Ahilyanagar

Rajmachiराजमाची
Western Ghats · Pune

David Scott TrailDavid Scott
Northeast · East Khasi Hills

Sandhan Valleyसांदण दरी
Western Ghats · Ahilyanagar

Dayara Bugyalदयारा बुग्याल
Uttarakhand · Uttarkashi

Har Ki Dunहर की दून
Uttarakhand · Uttarkashi

Rajgad to Tornaराजगड – तोरणा
Western Ghats · Pune

Tadiandamolತಡಿಯಾಂಡಮೋಳ್
Western Ghats · Kodagu

Kedarkanthaकेदारकांठा
Uttarakhand · Uttarkashi

Brahmatalब्रह्मताल
Uttarakhand · Chamoli

Kudremukhಕುದುರೆಮುಖ
Western Ghats · Chikmagalur

Kuari Passकुआरी पास
Uttarakhand · Chamoli

Doditalडोडीताल
Uttarakhand · Uttarkashi

Nongriat root bridgesNongriat
Northeast · East Khasi Hills

Dholkal (Bailadila)ढोलकल
Central India · Dantewada

Kumara Parvathaಕುಮಾರ ಪರ್ವತ
Western Ghats · Dakshina Kannada

Meesapulimalaമീശപ്പുലിമല
Western Ghats · Idukki

Pangarchullaपंगरचुल्ला
Uttarakhand · Chamoli

Goechalaगोएचा ला
Sikkim & Darjeeling · West Sikkim

Nag Tibbaनाग टिब्बा
Uttarakhand · Tehri
Also possible in December
Doable, but not the peak season: expect snow, rain or heat, as each trek page explains.

Prashar Lakeपराशर झील
Himachal · Mandi

Harishchandragadहरिश्चंद्रगड
Western Ghats · Ahilyanagar

Kareri Lakeकरेरी झील
Himachal · Kangra

Ali–Bedni Bugyalआली–बेदिनी बुग्याल
Uttarakhand · Chamoli

Dzükou ValleyDzükou
Northeast · Kohima

Dzongriज़ोंगरी
Sikkim & Darjeeling · West Sikkim

Chopta Chandrashilaचंद्रशिला
Uttarakhand · Rudraprayag