Thamel is Kathmandu's tourist district — a dense, disorienting grid of guesthouses, trekking agencies, outdoor gear shops, restaurants, and bars that has served as base camp for travellers heading to the Himalaya since the 1960s. It is unapologetically a bubble, but it functions well as one: you can find everything you need for a trek, a night out, or a quiet breakfast within a few blocks.
The streets are too narrow for the volume of taxis, motorcycles, and delivery vehicles that use them, which means Thamel is best explored on foot — and much of what's worth visiting is only findable by walking the alleys rather than sticking to the main roads. After dark the area around the Kathmandu Guest House gets lively; there are clubs, live music bars, and rooftop restaurants with views over the jumble of buildings.