Lake Chuzenji (中禅寺湖) is about one hour bus trip from the Nikko station. If you get off the bus one stop before Chuzenji Onsen, at Akechidaira (明智平), you could get onto a cable car for the great views of Lake Chuzenji and Kegon Falls. The hiking trail leads from there to the lake, via Chanokidaira (茶ノ木平). The trail was difficult to find and follow in some places - as there were almost no trail markers and in some areas the trail was completely overgrown by almost shoulder-high vegetation. There are also some discrepancies in the information available - guide books say that it is a '1.5 kilometers stroll', but I first had my suspicions when the guy at the cable car station gave me a map (after I've purchased only one way ticket) and said that it is 3 hour hike to the lake. I did make it in two hours - but it is definitely not a 'pleasant walk' and it is very easy to get lost there... However, it was absolutely worth it - as I've only met two people on the trail (who were actually lost) and no one else. Looking on the photos available on the Internet - the views from Chanokidaira, whilst still spectacular, used to be better - as now trees have grown up and you cannot see as much as before...
Nikko (日光市) contains may great temples and shrines, but as I was (and still am, I think...) "overdozed" on them, I've only had a brief 'walk-through', on the way back to Osaka - in fact I only wanted to see the Shinkyo Bridge (神橋 - Sacred Bridge). It is actually possible to walk on the bridge, for a fee, but I've opted not to...