A lot of train tracks intersect in Niles, just west of  Niles Canyon.
Alameda Creek, which widens in this area from its size in the Canyon, runs through here.
There are also a series of lakes from previous quarry activity.
The following sequence of pictures is taken going west to east through this area.

Train trestle going across Alameda Creek.  The Ace Train has just switched off of the track that continues in the foreground and is curving onto another track.  Looking West as the train travels Southwest

The trestle can be seen again, along with the two tracks that cross in an "X"  I am told that this is called a "Frog" in railroad terms.

View across the trestle, looking down the tracks.  The "X" (Frog) crossing is can be seen, just above where the branch at the left comes out.  Just after that is the trestle over Alameda Creek. 
The Ace Train is crossing these tracks at about a 45 degree angle.  It appears like a 90 degree angle, but the picture was taken looking back.  The lower right corner of the picture shows a bit of the bottom of the window to give perspective.  The track branch which switches off and goes to the left will quickly merge onto the track which the Ace Train is currently on.  The picture is taken toward the North West, with the train car in the middle of an S curve, temporarily going almost straight south.
The Nile Canyon Railway ends its run just on the other side of Alameda Creek, but not on any tracks that are visible here.  Its tracks come out of the canyon on the other side of the creek.
 

One of the Quarry Lakes.  A train track runs on the other side of the lake (the white looking poles toward the right are railroad signals).  This is the same track that is crossing right to left at the top of the above picture.  Alameda Creek is not visible, but is just beyond the train tracks.  The picture is taken to the North, and probably slightly West.

An old rusty steam engine on the North side of the tracks.  This is still in the Niles area, on the North side of the track.
 

Fremont's Centerville Station.  This is one of the old stations.  It was restored from 1998 to 1999.
Link to the history of the Centerville Station.  Includes lots of photos.
 

Next

Ace train icons by Don's Depot.