Normally S-Bahns are a form of light interurban rail networks
S-Bahns are not trams or tram trains, but are heavy rail. They are basically upgraded regional or commuter lines, which run on a common corridor through the city to allow for metro like frequencies on that section. A lot of the lines hav 20min frequency, but often share track to increase that. Quite a few of them are pretty close to metros. Not just the Berlin one. Hamburgs has 10min frequency on its lines for the most part, Cologne and the Rhein-Ruhr one is at 20-30min and a lot of shared track.
There are some, which are worse, but Berlins system is not an anomaly in being rather metro like.
Same in Frankfurt. In the city the frequency is quite high and then they split into lines when they get outside, which only reach a 30min frequency during rush hour I think.
Even the connection Frankfurt central station to Offenbach market place (city on the other river side) can reach a train every 5min during rush hour.
But they can get delayed when they surface and get outside.
S-Bahns are not trams or tram trains, but are heavy rail. They are basically upgraded regional or commuter lines, which run on a common corridor through the city to allow for metro like frequencies on that section. A lot of the lines hav 20min frequency, but often share track to increase that. Quite a few of them are pretty close to metros. Not just the Berlin one. Hamburgs has 10min frequency on its lines for the most part, Cologne and the Rhein-Ruhr one is at 20-30min and a lot of shared track.
There are some, which are worse, but Berlins system is not an anomaly in being rather metro like.
Same in Frankfurt. In the city the frequency is quite high and then they split into lines when they get outside, which only reach a 30min frequency during rush hour I think.
Even the connection Frankfurt central station to Offenbach market place (city on the other river side) can reach a train every 5min during rush hour.
But they can get delayed when they surface and get outside.