Further development

Since 1884 the Homburg Railway begins at Frankfurt West station

The Prussian annexations after the War of 1866 simplified the situation for the railway. The whole route now ran through Prussia, except for one small piece at Weißkirchen station. The closing of the casino by the Prussian state in 1872 led to a significant fall in passenger numbers. In 1873 and 1874 the Kronberg Railway was built by a private railway company: it branched off after Rödelheim to Kronberg.

On 1 January 1880 the railway was sold to Prussia because the company could not afford and did not want the changes to the line required for connection to the planned new Frankfurt Hauptbahnhof. It thus became part of the Prussian state railways. The line was diverted to connect at Bockenheim station (now Frankfurt West), which had to be avoided in 1860, on the also nationalised Main-Weser Railway. The diversion, opened on 10 May 1884, shortened the line to 15.6 km from Frankfurt West. The old line through the vineyards was removed.

Extension and expansion

Old station in Homburg

In 1895, the Usingen line from Homburg via Friedrichsdorf to Usingen was opened and some years later extended to Weilburg and Wetzlar on the Lahntal railway. In Homburg a second terminal station (Homburg Neu, new Homburg) was built in Louisenstraße, 200 to 300 metres from the first station, on the site of the current town hall. A link line between the two stations enabled shunting. Planning of a line to Friedberg began in 1868, although construction did not start until 1898 and the line was commissioned on 15 July 1901. It branched off the line to Usingen in Friedrichsdorf.

New Homburg station

In 1907, the old Homburg stations were replaced with the current station, creating a through line to Friedrichsdorf. In 1912, Homburg was renamed Bad Homburg. Between 1907 and 1912 the entire route from Frankfurt to Friedrichsdorf and Friedberg was duplicated.

Connecting curves

On 1 September 1905, a link was opened at the request of Emperor Wilhelm II through the Frankfurt vineyards (Rebstockgelände), initially only for freight and special trains. It branched off the Homburg line south of Rödelheim towards Höchst and was used from 1908 by passenger trains on the Bad Nauheim–Wiesbaden line (Bäderbahn, Spa Railway) between the spa (German: Bad) towns of Wiesbaden, Bad Homburg and Bad Nauheim. A link between this line and Frankfurt Hauptbahnhof was opened on 15 March 1927 and is still used by trains connecting to the Taunusbahn to the north of Bad Homburg. The curve from Homburg to Höchst was demolished in 1963 during motorway construction.

After 1945

After repairs to war damage the line recovered its importance for handling commuter traffic to Frankfurt. On 23 May 1954 a regular interval half-hourly timetable was introduced, initially hauled by class 78 steam locomotives and class V 80 and later V 100 diesel locomotives. The extension to Friedberg was downgraded to a single-track branch line due to war damage and a loss of profitability.

Following the completion of electrification on 26 September 1970 services were usually operated by trains hauled by class 141 electric locomotives. From 25 September 1977 S-Bahn services were operated by electric multiple units of class 420 terminating in Friedrichsdorf. Since 2003 the newer class 423 trains have operated on the line.