Medical devices for navigation through anatomy, including guidewires, which may have a core wire, a slotted tubular member, or both. Embodiments may have coils, including non-circular cross-section edge-wound marker coils, extended coil tips, and s soldered or glued mesial joint coils. Core wires may have a step, ridge, or taper at the joints to the tubular member, and may be flattened at the distal tip. Radiopaque material may be located inside the tubular member, and the distal tip may be heat treated to make it shapeable. Additional tubular members or coils may be used concentrically or in line and may enhance flexibility, provide radiopacity, reduce friction, or reduce material or manufacturing cost. Tubular members may be chamfered or tapered continuously or incrementally. Slots may be arranged in groups, such as groups of three, and may be equal in depth or unequal in depth to provide a steerable or compressible tip.