Complex sentence: Now the summit is ascended by an average 20,000 mountaineer-tourists each year and could be considered an easy, yet long, ascent for someone who is well trained and used to the altitude.
Split into simpler sentences: Now the summit is ascended by an average 20,000 mountaineer-tourists each year. It could be considered an easy, yet long, ascent for someone who is well trained and used to the altitude.