Start at Forest Research Institute around 9:00 AM, when the grand New Forest campus is cooler and quieter. Allow about two hours for the colonial main building, its forestry museums, and a stroll beneath the mature trees. The museums commonly operate during daytime hours, but timings and entry fees can change; budget roughly ₹20–₹100 for entry and carry photo ID if requested. An auto-rickshaw or cab from central Dehradun usually takes 20–30 minutes; the campus is spacious, so wear comfortable shoes and avoid arriving too late in the day.
From FRI, take a cab toward Pacific Mall in Jakhan—expect roughly 25–35 minutes depending on Rajpur Road traffic. Spend late morning browsing and cooling off indoors for about 1½ hours; the mall generally opens around 11:00 AM, with cafés and food outlets continuing later. It is a useful pause before heading farther along Rajpur Road, especially in August when rain can arrive suddenly.
Have lunch at Kumar Sweets on Rajpur Road, allowing around 45 minutes and ₹250–₹500 per person. Try local-style savoury snacks alongside North Indian sweets rather than making this a heavy meal, since the afternoon involves walking in water. From here, a cab to Robber’s Cave (Guchhupani) in Anarwala takes about 25–35 minutes. Plan 1½ hours to walk through the narrow limestone gorge and shallow stream; wear sandals or quick-drying footwear with good grip, keep phones in a waterproof pouch, and avoid entering during heavy rain or rising water. The approach has small stalls and can be busy, so late afternoon is usually more pleasant than midday; carry some cash for entry and refreshments.
Continue by cab from Robber’s Cave to Tapkeshwar Mahadev Temple in Garhi Cantt, generally 20–30 minutes depending on traffic. Give yourself about an hour to descend to the riverside cave shrine, see the naturally dripping ceiling, and sit quietly beside the seasonal stream. Dress modestly, remove footwear before entering the shrine, and keep a little cash for offerings. Afterward, autos and app cabs are easier to find back toward central Dehradun than directly at the cave, so arrange your return ride while you still have mobile reception.