Nearest airport to ARIES is Pantnagar , around 60 km from Nainital. The airport is well connected with IGI New Delhi and Dehradun through national carriers like air-india etc.
Other nearest airport is Lucknow, which is well connected to major indian cities.

Kathgodam (~35 km from Nainital) and Lal Kuan (~55 km from Nainital) are the nearest railway stations for Nainital. Some of the important train connections from Kathgodam:
1. Ranikhet Express (Jaisalmer - Jaipur - Delhi - Kathgodam) - daily
2. Sampark Kranti Express (Delhi-Kathgodam) - daily
3. ANVT KGM Shatabadi Exp(Anand-Vihar, Delhi - Kathgodam) - daily
4. Bagh Express (Howrah - Gorakhpur - Lucknow - Kathgodam) - daily
5. Lucknow - Kathgodam Express (Lucknow - Kathgodam) Sun-Wed-Thu from Lucknow
6. Agra - Ramnagar Express (Agra - Mathura- Bareilly - Lal Kuan) Weekly (Wed)

Nainital is connected by road to major centers of northern India, some of the major road distances are: Agra - 379 km. , Delhi - 277 km. and Bareilly - 141 km.

Tip for using taxi from Kathgodam-ARIES:
Once you reach at Kathgodam railways station, you can also take taxi to ARIES, which taxi drivers usually know as Observatory. For ARIES, there is bifurcation road on Kathgodam-Nainital high way, 6 km before reaching Nainital. The bifurcation road is about 3km, because of which, some time taxi driver charge Rs 25-50 extra for Kathgodam-ARIES as compare to Kathgodam-Nainital. The typical share basis taxi fair may be around Rs 100-150 per seat, and full taxi may cost around Rs 500-700 (also highly vary depending on the number of tourist visiting Nainital).

Institute bus service is also available from Nainital bus stand to ARIES, the bus timings are 8.30 AM, 9.40 AM, 1:00 PM, 2:30 PM, 4:00 pm and 7:00 pm and similarly from ARIES to Nainital at 9.00AM, 11:30AM, 2:00PM, 3:30PM and 5:30 pm.