This is a unique tourist attraction - it's a bit pricey to get to, and entrance is S7 by taxi (the only way if you don't walk), but if you're fairly fit, you can get a moto taxi for around S1.5 to the bridge about 10 minutes from Urubamba town, and walk about 40 minutes up to the salt flats, without having to pay entrance fees. Salineras is not included in the tourist ticket that you may get from Cusco - so by car you would have to pay separately. If you just want to see Salineras, and are not bothered/don't want to pay for Moray (which is normally toured simultaneously), I would recommend this route to save money.
To get to Moray, you can walk another 1.5-2 hours uphill to Maras and get a return taxi for around S25...but there's not a lot to see in Maras town, so it might be better to try and get a taxi from Salineras itself...some taxi drivers are rather misleading, saying that there aren't any taxis to Moray from Salineras, but that is definitely not the case. Although, if you're planning to see Moray and Salineras, it may be better to get a bus from Urubamba to Maras, and then get a return taxi to Moray before walking from Moras to Salineras downhill instead of up.
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