Later he served in the Israeli army as a member of the elite commando unit, Sayert Matcal. Following his army service he trained in a Swiss climbing school where he gained experience exploring the French and Swiss Alps. Soon he was also climbing in the Sinai and Alaska.
In 1987 he became the first Israeli to summit Alaska's Mount McKinley. In 1989, he led the first group of Israelis permitted to climb in Communist Russia—the group was accompanied by a KGB agent.
In 1992 Erel became the first Israeli to summit Mount Everest.
In the following years he climbed the "Seven Summits," which are the highest peaks on each continent, an exceedingly rare achievement. After that his activities included kayaking in Greenland and dog sledding on Baffin Island.
He has been active in Alpine rescue operations, including a search for survivors of the 1990's Lenin's Peak avalanche, which was the worst disaster in climbing history and where upwards of 40 people were killed.
In 2004, Erel participated in an expedition called Breaking the Ice, in which four Palestinians and four Israelis worked together to climb an unconquered mountain in Antarctica. The primary purpose of the expedition, organized by Extreme Peace Missions, was to prove that people from different political and religious backgrounds can co-operate with each other. The group eventually reached the summit and named the peak ""The Mountain of Israeli-Palestinian Friendship."
His other activities have included introducing mentally challenged youths to the world of mountain climbing; volunteer work in prisons; and lecturing on climbing and motivation to the Israeli army and air force, the Mossad and various business and educational groups.
Erel maintains a website, www.doronerel.co.il, where you can learn more about him.