The city of 
Sandpoint, in the Idaho panhandle, is situated at the north end of 
Lake Pend Oreille, where the lake then feeds into the Pend Oreille River.  I picked out a couple trails that each start near the downtown area - the 
Long Bridge Trail and the 
Pend Oreille Bay Trail.  I'll cover the Long Bridge Trail this time, and the Bay Trail next time.  Here's a 
GPS trace of the route.
Summary
Also known as the Serenity Lee Trail, this trail crosses a 2-mile bridge that parallels US highway 95.  The bridge itself has quite a history - you can read about it, and see old photos, 
here.  Although listed as a Rail Trail on TrailLink.com, it is not.  Starting from the north, it does parallel the BNSF Railroad, but it soon diverges as they each cross the water.
|  | 
| I was pleased to find parking in the designated lot.  The bathrooms were open and clean. | 
|  | 
| Heading south, the railroad diverges from the trail.  There was a lot of rail activity on this day. | 
|  | 
| Along the shore just south of Sandpoint, ID. | 
|  | 
| The Long Bridge, which was the old US 95 until they built the new bridge along side. | 
|  | 
| Looking east, you can see the BNSF railroad bridge in the distance, spanning the bay. | 
|  | 
| After crossing the bridge, there was a bit of hill-and-dale, with open space on the left.  US 95, on the right, was usually a comfortable distance away. | 
|  | 
| A fairly typical view looking east, with the Cabinet Mountains in the distance. | 
|  | 
| Another very nice view looking east. |