[Ann de IL]

Sorry, you are wrong. The rest areas are called rest areas. An oasis is a rest area that is on a bridge above and across the interstate. The only oasis I know of is near O’Hare airport where there really wasn’t enough land to build a conventional rest area.

[wtd]

"Sorry, you are wrong. The rest areas are called rest areas. An oasis is a rest area that is on a bridge above and across the interstate. The only oasis I know of is near O’Hare airport where there really wasn’t enough land to build a conventional rest area." - Ann de IL

Actually, I am correct that there is more than one. See here:

• The six Tollway Oases located along the Illinois Tollway system offer commuters and travelers a variety of convenient food options and a wide range of services.