IHG One Rewards. It's better to be a member. Join IHG One Rewards to unlock benefits that will immediately enhance your next stay. Welcome to the Holiday Inn Express Ottawa IL! Ottawa is a city located at the confluence of the navigable Illinois River and Fox River in LaSalle County, Illinois, United States. The Illinois River is a conduit for river barges and connects Lake Michigan at Chicago, to the Mississippi River and North America's 25,000 mile river system. We are just a few miles from Buffalo Rock State Park and Sky Dive Chicago, the premier sky diving location for all of Chicago!