Avoid cave entrances. Small overhangs can allow arcs to cross the gap. Natural caves that go well into the ground can be struck, either via the entrance or through the ground. You should never be anywhere near any metal handrail, wire or cable during a storm. Avoid trees because they are taller than their surroundings.
Tall trees are especially adept at generating streamers that attract strikes.
If you need to move through a forest while seeking safer terrain, stay away from the tree trunks as you move. You should also avoid open areas that are 100 m wide or wider. Avoid long conductors. Metal fences, power lines, phone lines, railway tracks, handrails, measuring tapes, bridges, and other metal objects can carry significant lightning current even if these objects are at some distance from the lightning ground strike point. Near the ground strike point of a lightning discharge, wet ropes can conduct lethal currents.