[Completion of the Railroad, Nine Mile Gap Mail] San Francisco May 6 (1869) postmark on unpaid folded letter to Cognac, France, this letter would have transited by rail to Corinne, UT and then by Wells Fargo stage for 9 miles to the railhead at Indian Creek, UT to the eastern railhead, the rail link was completed on 10 May 1869 (this first through trip departed San Francisco Monday, May 8), letter departed New York on 15 May 1869 departure of French Packet Lafayette, French Line departure date postmark and French transit and arrival backstamps
 

ex Walske

[Via California and trans-continental RR to Swatow] 10c Green (#68) tied to Wingate correspondence cover to Swatow, China, Stratham, NH May 28 1869 origin postmark and endorsed "Via California" at top, New York transit and instead of a NY exchange, it could now transmitted on the newly completed Trans-continental railway to the San Francisco, Cal exchange office, their magenta "Jul 3 Paid All" exchange, carried on PMSS steamer Great Republic via Japan to Hong Kong, "Hong Kong 6 Aug 69" transit and "A Swatow Aug 7 69" arrival backstamps, an early use on the new routes (image of reverse here)

[South Pass City, Wyoming, 1869] South Pass City Wy. Ty Jun 30 1869, year dated Wyoming Territory origin datestamp on cover with 3c 1869 issue #114) tied, address to Stoughton, Mass where it was re-mailed to Foxboro with a second 3c ultramarine, an early use on the completed T-C railroad

ex Kramer

[Helena, Montana Hotel Cover, ca. 1869] International Hotel, Helena, Montana Territory all over illustrated advertising cover in brown used with 3c 1869 (#114) from Salt Lake City Utah Territory, their "Jun 29" duplex postmark

ex Walske and Kramer

[Union Pacific R.R.] July (1869) postmark with indistinct date on unpaid cover to Paris, France, carried on the Inman Line steamer City of London that departed New York on 24 July, blue Calais French entry postmark, Paris arrival and "8" decimes due, cover tear at left, a rare use to a foreign destination that entered the mails to a railroad route agent
 

ex Noel and Walske