I want to remove some layers from the osm map of an area. It has all the details like POI, offline routing and all. But I just want the map data. How can I remove this extra layer from the map?
There are no layers as such. You have points (=nodes), lines (=ways) and relations between those. They can have attributes (=tags), which represent map features. If you want to have a map of just the features you're interested in, you can use tools like TileMill or Maperitive to generate such maps. It all depends on your concrete needs - do you need a Web map, a bitmap, a vector map...