The Sierra Nevada de Santa Marta (SNSM) in northwestern Colombia is one of the world’s highest coastal mountains, with an elevation above 5.7 km. Gravity measurements show that the SNSM has a high Bouguer anomaly (>+130 mGal), indicating that the mountain lacks a crustal root. In this work, we test the hypothesis that these observa- tions can be explained by gravitational removal of the dense lower lithosphere. We use 2D numerical models to examine the dynamics of lithosphere removal and its effect on surface elevation, gravity and heat flow. The models consist of continental lithosphere that includes a pre-thickened crustal region, representing the SNSM. In our preferred model, the dense mantle lithosphere instability and crustal root are gravitationally unstable and undergo removal as local drips within ∼10 Ma from the onset of foundering. This cre- ates an area of thinned crust (∼38 km) underlain by a buoyant sublithospheric mantle where melting and low seismic velocities are predicted. Subsequent non-isostatic forces maintain a topography of 3.3 km with a Bouguer gravity anomaly of +103 mGal. Pa- rameter tests show that a strong lower-crustal rheology provides greater support for the high topography and that a weak mantle lithosphere rheology produces faster removal. The models demonstrate that local lithosphere dynamics can explain the first-order ob- servations in the SNSM. We propose that lithosphere removal could have occurred at 40- 50 Ma, possibly inducing anomalous short-lived Eocene magmatism, or more recently (∼2 Ma), explaining the localized low seismic velocity zone below the SNSM.