Adding a C/C++ nature to an Eclipse project

Does anybody know how to add a C/C++ project nature to an Eclipse project through the UI ? I'm importing a project and working with legacy code that was originally started in Visual Studio 4 and I'd really like to be able to make as much use of Eclipse's helpers as possible.

Assuming you've got the CDT plugin installed

Right-click on the project.

Select: New -> Other

Under C/C++, select "Convert to a C/C++ project"

Create a new C project using the existing source code.