Kusatsu’s famous emerald crater lake, Yugama, was finally reopened to visitors in October after more than eight years off-limits. The reopening lasted just seven days before the town shut access again, not because of volcanic activity, but because the sheer number of visitors overwhelmed the road leading to it.
The burdens of tourism
The thing is, reopening a popular tourist destination takes more than being “safe.” You also need enough parking, working facilities, and a way to keep traffic moving, since many people tend to arrive at the same time.
Near the summit of Kusatsu-Shiranesan on the Gunma-Nagano border, Yugama has striking emerald-green water in a volcanic crater surrounded by stark, rocky slopes. Together with Kusatsu Onsen, the famous hot-spring resort town below, it’s one of the main reasons people visit the region.
However, travelers hoping to see the lake this autumn will have to wait a bit longer.
Why was Yugama closed for eight years?
Yugama’s long closure began in April 2018, when the Japan Meteorological Agency (JMA) raised the volcanic alert level for the crater area to Level 2. Japan uses a five-level volcanic alert system, and Level 2 means: don’t go near it.
Although the alert level eventually dropped to Level 1, lifting crater-access restrictions, the lake remained closed to visitors. The JMA still warned that small-scale ash emissions are possible within approximately 500 meters (~1,640 feet, or roughly 4.5 football fields) of the crater. So, you can imagine why the town would want to play it safe and keep people away.
These volcanic warnings aren’t for nothing, either. In January 2018, an eruption at nearby Mount Motoshirane killed one person and injured 11 others. Though the two peaks are separate, officials likely decided it’s better to be safe than sorry.
By May 2026, the JMA had finally lowered the alert level, paving the way for Kusatsu to try reopening the area.
An opening trial runs into trouble
The town launched its reopening trial on October 13. Visitors could walk along a roughly 610-meter trail to a viewpoint approximately 550 meters from the crater.
The arrangements were relatively straightforward. The nearby Shirane rest house parking lot offered free parking for about 240 cars and 20 large vehicles. People could enter between 10 a.m. and 3 p.m., and had to leave by 4 p.m. Three or four safety guides were supposed to help manage the area.
On opening day, nearly 300 people lined up to see the lake. Some had traveled from Chiba and Kanagawa, while others came from neighboring Nagano Prefecture. For visitors who had assumed they might never see Yugama again, the reopening was a rare opportunity.
Unfortunately, it presented the area with a new problem: traffic.
When the rarity of visitation beckons crowds, traffic jams ensue
By 7 a.m. on October 17, three hours before the parking lot opened, cars were already waiting to get in. Kusatsu issued an urgent warning asking people to reconsider visiting over the weekend. Officials cautioned that vehicles queuing on National Route 292 could cause traffic jams, delay staff, and increase the risk of rear-end collisions.
People either didn’t hear the warning or didn’t care. According to Gunma TV, around 2,300 cars arrived on both October 17 and 18. Traffic jams stretched as far as 7 kilometers. We wrote recently about how residents of the Soni Plateau in Nara Prefecture faced the same problem.
The town brought in more than three times its planned staffing level, but additional personnel could not fix the underlying problem. That being, there simply wasn’t enough space to accommodate everyone in a timely fashion.
Toilets became another bottleneck. Since the rest house’s shops and restaurants were closed during the trial, there just weren’t enough toilets for all the visitors.
Why Kusatsu pulled the plug: operational issues
On October 19, the town ended the reopening trial, but the reason was less “overcrowding” and more “emergency access.” The traffic jams were backing up National Route 292, a two-way road with one lane in each direction. It’s a road that connects neighboring communities and provides a route toward Nagano.
With congestion as bad as it was, officials could not guarantee that emergency vehicles would be able to pass or that people could evacuate efficiently if volcanic activity changed.
But just to be clear, the town explicitly stated that the suspension was an operational decision and had nothing to do with volcanic activity.
Mayor Miyazaki Kimio said it was a hard decision to make because clearly so many people wanted to come visit. And unfortunately, the town has not announced when access might resume or what a future reopening would look like.
Reservations or buses? Possible ways to cope with crowding
The demand to visit Yugama shouldn’t be a surprise. In 2024, Kusatsu planned a series of reservation-only guided tours. Some 400 people booked before the program was canceled after a JMA advisory warned of potentially increased volcanic activity. The 320 October spots sold out in less than 10 minutes.
Volcanic craters present a unique and dangerous beauty, so it’s no surprise they’re so popular.
Some commenters responding to the latest closure suggested timed reservations, lotteries, or shuttle buses from parking areas farther down the mountain. Another possible model is the Kiyotsu Gorge Tunnel in Niigata Prefecture, which introduced advance reservations on busy days to address crowding and parking shortages.
The town hasn’t said yet what it will do; presumably, it’s still sorting out what would work best.
Can you visit Yugama this autumn?
For now, the answer is no. The Yugama trail area and its trial parking lot have been closed since October 20. However, National Route 292 remains open, so visitors can travel along the scenic road between Kusatsu and Shiga Kogen and at least catch a glimpse of the mountain range.
Kusatsu says it will review traffic management, evacuation procedures, facilities, and coordination with other authorities before deciding what happens next.
If nothing else, Yugama’s brief reopening showed just how much people wanted to see the lake again. The challenge now is letting visitors come without turning a scenic mountain road into a safety hazard.
Keep reading
Sources
渋滞で「湯釜」観光中止、草津町 8年ぶり解除から1週間で 共同通信（47NEWS）
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Kusatsu-Shirane volcano eruption on January 23, 2018, observed using JMA operational weather radars ResearchGate
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草津白根山「湯釜」が8年ぶりに見学可能に! 初日から多くの人が訪れ、周辺道路で渋滞も発生 BRAVO MOUNTAIN（Yahoo!ニュース）