The Oberer and unterer Mattbachfall are two separate waterfalls in the same river at the end of the Weisstannental near Mels in the region Sankt Gallen, Switzerland.
From Mels drive into the Weisstannental to Weisstannen. There cross the bridge and go right onto a narrow road. After a few kilometer the road ends at a house and parking (gps 46.967617, 9.270578).
From the parking you already have a good view on the Isengrindfall but to see both Mattbachfall you have to walk a little to the unterer Mattbachfall.
The Weisstannetal is anyway a very thankful valley if you want to visit waterfalls. There are dozens of unnamed waterfalls but also seven named waterfalls.