OK I've figured it out. In the City of Toronto, there are numerous duplicate street names caused by amalgamation. See <http://finance.groups.yahoo.com/group/ontroads/message/9826>. If there is a duplicate street name, you must use the name of the former municipality in the address e.g. York, East York, Etobicoke, Scarborough, North York. If it is not a duplicate, either "Toronto" or the name of the former municipality are acceptable. Various other city names like Downsview, Don Mills and Weston are acceptable for certain areas of these former municipalities, these are generally just aliases for the old municipality name (though Downsview for instance is only accepted for the portion of North York near the community of Downsview, using "Downsview" for an address at Yonge/Sheppard is incorrect).
In Markham, there is the weird situation of "Main Street Unionville" and "Main Street Markham". In other parts of the GTA, sometimes the city name used by the post office doesn't match the actual city's name, but I can't find any other examples of duplicate street names other than the one in Markham. If an address is "Woodbridge" or "Concord" we can pretend it is in Vaughan. Since the Canada Post database is proprietary I have had to figure this out from sources like receipts from coffee shops and fast food restaurants. Fortunately these are easy to get. Is a free source available for the boundaries of Old Toronto, North York, York and East York as they existed before 1998? I have added the boundaries of Scarborough and Etobicoke as boundary=administrative, admin_level=10 which seems to make nominatim work propertly (though it says that the addresses are in Scarborough, Toronto, Ontario, Canada instead of Scarborough, Ontario, Canada which is not the correct format). _______________________________________________ Talk-ca mailing list Talk-ca@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk-ca