Valentine Lake Tail is a relatively difficult, 10 mile (out and back) hike with an elevation gain of over 2000 feet. It is probably the most strenuous hike in the immediate Mammoth Lakes area. There are plenty of more difficult hikes you can find that are within a 30-45 minute drive, but the Valentine Lake trailhead is just outside of town and is easy to get to. You will want to bring all your day-hiking essentials, plenty of water, and something to eat when you get to the lake.
This trail connects with the Sherwin Lake Trail (see our review of that trail) and some people like to start there, but we prefer to go to the Valentine Lake trailhead because less people park there. Get to the trailhead by going down Sherwin Creek Road from Old Mammoth Road. You will pass the turn off for Sherwin Lakes Trailhead and keep going a few miles after it turns to a dirt road. You will see a small sign pointing to the small dirt parking area right in front of Sherwin Creek. Keep any out, it is easy to miss.
You likely won't see to many other hikers because most people visiting Mammoth Lakes for hiking hit the more well known or easier trials around town. Make sure you put on sunscreen and wear a good hat because the first few miles are totally exposed and the sun beats down pretty good in this difficult section of trail. Most of the elevation gain takes place early on and when it is hot it can be an extremely tough start to a long hike. The nice part of this section of switchbacks is the awesome views of the whole Owens Valley to take in while you take water breaks.
Once you get over the first set of ridges the trail mellows out with only slight inclines until you get closer to Valentine Lake. This section is where the trail meets up with Sherwin Lakes Trail and it is possible to do a loop back to your vehicle if you don't mind walking a few miles on the dirt road between the two trail heads. There are tons of really cool gnarled trees and great views of the various mountain ranges surrounding the area, so take your time and enjoy being in John Muir Wilderness.
As you continue down the trail you get into a lot more foliage and eventually into a more forested area. There are a couple easy water crossings along this section of trail and you really start to feel like you are in the middle of nowhere. You will know you are getting close to the end of trail when you come across a rather large pond that I don't think has a name, but don't mistake it for Valentine Lake. The trail continues along a creek with about 20 switchbacks and a good amount of elevation gain just before you get to the Lake. When you get to the top, head to the right side of the lake if you are looking for a more open area to hang out before you head back. If you are looking for a challenging hike, close to town, without too many other hikers this is a great option.