Draw a tile map efficiently

My level is a grid of tiles: <describe size and tile size>

- Store the map as a simple array I can edit by hand — ideally
  readable as text.
- Draw only the tiles currently visible, computed from the camera.
  Don't loop the whole map every frame.
- Tile lookup for collisions: given a world position, which tile?
- Handle the map being larger than the visible area in both axes.

Then tell me at what map size this approach stops being fast enough,
and what I'd do then.