Complex sentence: In total the company operates 140 km (88 miles) of metre gauge track, 42 km (24 miles) of standard gauge track, and a short rack railway, in the Pyrenees mountains.
Split into simpler sentences: In total the company operates 140 km (88 miles) of metre gauge track, and 42 km (24 miles) of standard gauge track. And also operates a short rack railway, in the Pyrenees mountains.