Rule for masculine · der
Vehicles like ICE are der (a very rare rule).
Certain means of transport, like der ICE (Germany's high-speed train), take the masculine gender. This is an extremely rare rule in our course - just one word out of 2,400 falls into this category, so treat it as a useful note about this specific word rather than a general pattern. There are no known exceptions in our data, but with only one example that isn't saying much - the simplest thing is to just remember der ICE directly.