| Key | Value |
| air_conditioning | yes |
| building | yes |
| fax | 0955-58-8382 |
| internet_access | wlan |
| internet_access:fee | no |
| name:en | Riverside Inn Karatsu Castle |
| payment:DC | yes |
| payment:american_express | yes |
| payment:jcb | yes |
| payment:mastercard | yes |
| payment:visa | yes |
| phone | 0955-58-8381 |
| tourism | guest_house |
| website | https://www.karatsu-castle.com/ |