Colour world imaging expose your digatal image onto photographic paper i.e not an inkjet printer but a real photo. you will not get better than this. it is archival and claims to be fade resistant for 75 years!
i use them all the time, they will give you technical advice and provide you with there printer profile to import into your software to get accurate colour reproduction. this is very important for landscapes.
http://www.colorworldimaging.co.uk