The study reports the discovery of superconductivity at a record temperature of 250 K in lanthanum hydride (LaH$_{10}$) under high pressure. This finding is significant as it represents a leap of about 50 K from the previous record of 203 K in H$_2$S. The superconductivity was confirmed through zero-resistance observations, isotope effects, and the decrease in critical temperature under an external magnetic field, suggesting an upper critical magnetic field of approximately 120 T at zero temperature. The pressure dependence of the transition temperatures shows a maximum at around 170 GPa, indicating the possibility of achieving room-temperature superconductivity (RTSC) in the near future. The research also highlights the potential of using crystal structure predictions based on Density Functional Theory (DFT) to guide the search for high-temperature superconductors. The findings contribute to the ongoing quest for RTSC and provide evidence that conventional superconductivity can be achieved at ambient pressure.The study reports the discovery of superconductivity at a record temperature of 250 K in lanthanum hydride (LaH$_{10}$) under high pressure. This finding is significant as it represents a leap of about 50 K from the previous record of 203 K in H$_2$S. The superconductivity was confirmed through zero-resistance observations, isotope effects, and the decrease in critical temperature under an external magnetic field, suggesting an upper critical magnetic field of approximately 120 T at zero temperature. The pressure dependence of the transition temperatures shows a maximum at around 170 GPa, indicating the possibility of achieving room-temperature superconductivity (RTSC) in the near future. The research also highlights the potential of using crystal structure predictions based on Density Functional Theory (DFT) to guide the search for high-temperature superconductors. The findings contribute to the ongoing quest for RTSC and provide evidence that conventional superconductivity can be achieved at ambient pressure.