The obvious destination from Gorkha is Manakamana. The old walking trail is increasingly ignored, now there’s a road, but you can still find the trail, starting from the unpaved side road off the main Gorkha road, 7km down from the town. It takes four hours to walk to Manakamana, and it’s easily possible to return via the cable car and bus the same day.
Longer routes can be found by taking the high trail through Hanuman Bhanjyang – this is the traditional start of the Manaslu Circuit trek. From the little pass, you descend gently for about ninety minutes to Ali Bhanjyang (where you can find tea and snack food); from here you can ascend along a ridge with fabulous views to Khanchok (about 2hr 30min). This would be about the limit for a day hike, but given an early start you could continue down to the subtropical banks of the Budhi Gandaki at Arughat, a long day’s 20km from Gorkha – and a third of the way to Trisuli. A rough road now connects Arughat to the town of Dhading, which is 21km up a surfaced side road from Malekhu, on the Prithvi Highway.