【Shimizu Shindо̄】
The Shimizu Shindō is a short nature trail that connects the two most popular trails in the Shiga Highlands, the Ikemeguri and the Shizen Tanshо̄ courses, to create a single loop. It starts at the Ōnumaike Iriguchi bus stop and passes over the Giant Ski Slope to the Shinshū Daigaku Shizenkyо̄ikuen bus stop. It covers 1.1 kilometers and takes about 40 minutes to traverse.
Despite its short length, the trail provides plenty to interest geologists and naturalists. Lava flows from the eruption 400,000 years ago that flattened Mt. Shiga into the Shiga Highlands are still visible among the shadows of rugged andesite boulders and primeval alpine forest vegetation at points along the path. The result is a primordial atmosphere that feels separated from civilization.
Hikers on this course can enjoy a panorama of the area around Naga Pond, which is filled with blackish-brown water. This natural murkiness is a result of its position at the bottom of tree-lined slopes. The fallen leaves decay into a black, loamy humus that is washed into the pond when it rains. While the pond might look polluted, it is actually a mineral-rich environment ideal for marsh plants such as sedge grasses and Shiga iris (I. sanguinea X setosa).
The area around the pond is one of the best spots for birdwatching in the Shiga Highlands. Particularly in May and June, when around 30 local species have their breeding season, the mornings are filled with birdsong.