This study reports the observation of an extremely large one-dimensional positive magnetoresistance (XMR) in the layered transition metal dichalcogenide WTe₂. The XMR reaches 452,700% at 4.5 K in a 14.7 T magnetic field and 2.5 million% at 0.4 K in 45 T, with no saturation. The XMR is highly anisotropic, maximized along the crystallographic direction where small pockets of holes and electrons are found in the electronic structure. The origin of this effect and the fabrication of nanostructures based on WTe₂'s XMR represent a new direction in magnetoresistivity research. WTe₂ is a TMD with a distorted MoS₂ structure. It is semi-metallic and has been studied for thermoelectric applications. The XMR in WTe₂ is particularly surprising as it occurs in a non-magnetic, non-semiconducting system. The XMR is highly anisotropic, with the largest values along the chain direction and a significant drop when the magnetic field is applied in other directions. The effect becomes significant below approximately 150 K, with the "turn on" temperature increasing with the applied magnetic field. The temperature-dependent resistivity under various magnetic fields shows a dramatic increase in resistivity below the "turn on" temperature. The XMR effect is extremely large, reaching 452,700% at 4.5 K in a 14.7 T field. The "turn on" temperature shifts with increasing magnetic field, indicating a competition between scattering mechanisms. Electron diffraction studies show no structural phase transition or charge density wave onset. The electronic structure calculations show WTe₂ as a semimetal with valence and conduction bands crossing the Fermi energy. The Fermi surface is sensitive to the Fermi level position, with electron and hole pockets along the Γ-X direction. The XMR is due to the interference between oscillations from hole and electron pockets. The one-dimensional nature of the XMR makes WTe₂ a promising material for low-temperature magnetic field sensing and orientation. WTe₂ is structurally one-dimensional and shows extreme one-dimensional anisotropy in its XMR. It is a layered TMD that can be easily exfoliated, making it suitable for thin films and nanostructures. The study also highlights the potential for further properties and applications of WTe₂, including electron gating experiments and chemical doping. The results suggest that WTe₂ is a promising material for future electronic and magnetic applications.This study reports the observation of an extremely large one-dimensional positive magnetoresistance (XMR) in the layered transition metal dichalcogenide WTe₂. The XMR reaches 452,700% at 4.5 K in a 14.7 T magnetic field and 2.5 million% at 0.4 K in 45 T, with no saturation. The XMR is highly anisotropic, maximized along the crystallographic direction where small pockets of holes and electrons are found in the electronic structure. The origin of this effect and the fabrication of nanostructures based on WTe₂'s XMR represent a new direction in magnetoresistivity research. WTe₂ is a TMD with a distorted MoS₂ structure. It is semi-metallic and has been studied for thermoelectric applications. The XMR in WTe₂ is particularly surprising as it occurs in a non-magnetic, non-semiconducting system. The XMR is highly anisotropic, with the largest values along the chain direction and a significant drop when the magnetic field is applied in other directions. The effect becomes significant below approximately 150 K, with the "turn on" temperature increasing with the applied magnetic field. The temperature-dependent resistivity under various magnetic fields shows a dramatic increase in resistivity below the "turn on" temperature. The XMR effect is extremely large, reaching 452,700% at 4.5 K in a 14.7 T field. The "turn on" temperature shifts with increasing magnetic field, indicating a competition between scattering mechanisms. Electron diffraction studies show no structural phase transition or charge density wave onset. The electronic structure calculations show WTe₂ as a semimetal with valence and conduction bands crossing the Fermi energy. The Fermi surface is sensitive to the Fermi level position, with electron and hole pockets along the Γ-X direction. The XMR is due to the interference between oscillations from hole and electron pockets. The one-dimensional nature of the XMR makes WTe₂ a promising material for low-temperature magnetic field sensing and orientation. WTe₂ is structurally one-dimensional and shows extreme one-dimensional anisotropy in its XMR. It is a layered TMD that can be easily exfoliated, making it suitable for thin films and nanostructures. The study also highlights the potential for further properties and applications of WTe₂, including electron gating experiments and chemical doping. The results suggest that WTe₂ is a promising material for future electronic and magnetic applications.