The event horizon of a black hole is indeed very cold. The temperature of the event horizon of a black hole is proportional to its mass. For a black hole with the mass of the Sun, the temperature of the event horizon is about 60 nanokelvins (nK). This is extremely cold, even compared to the coldest places in the universe. For comparison, the temperature of the cosmic microwave background, which is the remnant radiation from the Big Bang, is about 2.7 K.

It's important to note that the temperature of the event horizon does not mean that the black hole itself is cold. The interior of a black hole is not well-defined in general relativity, and its properties are still a subject of ongoing research.