The Holiday Inn in Spearfish, SD has got to be a former Holidome. I used to beg my parents to take me as a kid to a Holidome. My grandparents when they brought me along on a trip did book into Holiday Inns. He always looked for Holidome's for the trips.

Anyway the location in Spearfish, SD has a large indoor pool, arcade area and rooms facing the indoor pool. There is another section that was added on that is connected as well but the rooms are not in the interior section with the pool.

The interior section with the pool area has a strong smell of chlorine for sure. I would say there is a very strong chance that the location was a Holidome.