Radio astronomy offers a variety of ways to study the fundamental forces in the Universe.
Especially gravity can be uniquely probed by a variety of experiments. Here, I will described the
latest set of experiments, probing the strong-field aspects of theories of gravity as well as the
properties of black holes and gravitational waves. These experiments range from binary pulsar
tests, attempts to image a black hole event horizon and the direct and indirect detection of gravitational
waves.