Kusatsu or Karuizawa

Hello

I will be visiting Tokyo for work in April and I will have 2 free days (2 days, 1 night). I am planning on visiting both Kusatsu and Karuizawa and stay overnight in one of them. I have never been to both places. Would love your opinion if you'd rather sleep in Kusatsu or Karuizawa. I will be traveling by shinkansen/bus. I am open to rental-car suggestion as well. Not too big on shopping at Karuizawa outlet mall.

My plans are:
1. Arrive morning in Karuizawa, explore the city, stay overnight in Karuizawa. Check out the next day in the morning, head to Kusatsu and leave Kusatsu in the evening back to Tokyo

or

2. Arrive morning in Kustasu, explore the city, stay overnight in Kusatsu. Check out the next day in the morning, head to Karuizawa for lunch. Explore Karuizawa and leave around evening back to Tokyo.

or

3. Arrive in Karuizawa in the morning, explore the city, leave around 3 pm and head to Kusatsu to stay overnight. Explore Kusatsu during this night and the next morning and leave around evening back to Tokyo.

Would appreciate feedbacks and I am open to suggestions!

Thank you :)

I havent been to Kusatsu yet, but I've stayed at Tsuruya ryokan at Karuizawa a few times and really I think it is awesome, especially for people unfamiliar with ryokans. The rooms are good, the food is great, the owners lovely, the place is historical, and it is all very easy and not regimented, also the ryokan is up the top of the shopping street near the start of the trail to the lookout/temple. It gets a really huge recommendation from me, and I've stayed at maybe 20 plus ryokans over the years.

Don't really know what you're looking for in Kusatsu, but I came there for the onsens. I did not venture out beyond the onsen town. The yubatake and green water sure is a sight to see, but at the end of the day I was there to dip in hot spring and relax at the ryokan. If you don't want to stay overnight, you can also go to the public onsens or dip your feet in the public footbath. Fyi, the water in Kusatsu is much much hotter than the water where I stayed at in Hakone. Dunno what the norm is as those are my only 2 onsen experiences.

Kusatsu is a small onsen town, unless you intend to try some of the onsen, in which kustasu has one of the best and hotest in japan, you might consider trying some other places. if you are interested, you won't regret it, nice place with a good park that has spring water flowing out everywhere and the yubatake in the middle of the town look nice.

I recommend getting a rental car, many hotels have parking space, and it's a sight just seeing the countyside whiles driving there, but it will depends on where you are coming from.

2 years ago I stayed 2 nights in Kusatsu onsen, and took a direct bus from Kusatsu to Karuizawa.

If you love onsen, option 2 would be a good choice.