Riding on frozen lakes and ponds has to be one of the most idiosyncratic niches in the kingdom of the bike. It is not for everyone, yet, if properly prepared, anyone can do it. The effort to turn the cranks over a frozen, flat surface is minimal. The trick is doing all your homework. 

Safety is the number one concern. Dangers range from major head trauma to drowning in water just above freezing. 

There is nothing soft about thick ice. Hitting your unprotected head on it while falling from the height of riding position can result in cerebral edema and a one way ticket out of this world. You must wear a helmet!

Going through thick ice into deep, frigid water has to be one of the scariest things you could err on doing on a bike. Even if you get back to the surface and take in a lungful of air, you still have to get back onto the top of the ice. Heavy clothes soaked with water, you will weigh more than you can imagine. Even more precarious will be your inability to get enough traction on the shelf of ice to pull yourself on top of it. That's not including in the process you can break off pieces of ice on which you are trying to alight. Prudent skaters and ice fishermen wear a device with 2 sharp picks connected by way of a chord when they venture on open ice to grip the broken ice shelf and self-rescue. You should as well. Look up Ice Awls and its ilk online. This purchase can save your life. Going one step further, wear a floation device, some of which are inflatable. Ice fisherman will frequently wear survival suits. These bulky one pieces are well suited to their non-aerobic sport, but not to ours.

Thus the discipline of determining whether ice on prospective ponds and lakes are safe enough to ride. How open bodies of water freeze, and what the composition of the ice shelf constitutes is beyond the scope of this introduction. What you as an enthusiast needs to understand it that determining safety is extremely complicated. The shelf will vary in thickness and in density. Just because you see people out on the ice does not mean every section is safe. You cannot judge this book by its cover. Wind, water flow and cover with snow will all affect thickness and density.

Harriman State Park allows activities on some of its frozen lakes and ponds, which they vet, flying flags: green for safe, red for forbidden. Most users are ice fishermen. Seeing then out on ice is an excellent metric for safety. Ask them how thick the ice is. From a Minnesota website:

There needs to be a certain amount of time below the freezing point to obtain a safe, frozen surface. Generally, you lose 3 degrees of Fahrenheit for every thousand feet of elevation. Therefore, the greater the altitude, the thicker the ice. This is especially important early in the season. Add to this that temperatures are generally cooler the further north and west you go from the city; the upper reaches of West Point and Black Rock Forest satisfies this concern while being within striking distance from rail lines. 

The second ingredient to riding on ice are studded, carbide tires. As mentioned, the actual turning of cranks to propel the bike is easy. Any bike will fit the bill as long as you have these tires. Efficiency of studded tires vary. Wider tires offer a greater footprint on the surface. Lower tire pressure can help engage more studs. Tubeless tires offer lower pressure without risk of pinch flats encountered in accessing your venue. Consider that any mechanical, flat tires included, in cold weather can become a life threatening issue. Fingers do not work well in cold. Rubber contracts, making it a magnitude harder to work than in mild temperatures. You must have an impeccable bicycle to consider riding on ice. You need to have thought out contingency plans. You need to carry extra clothes. Chemical hand warmers are aces, just keep them dry during use. A backpack with a mylar blanket or 2 inside is the way to go. The backpack will also protect your spine should you happen to fall, landing on your back.

Putting your foot down while riding on glaze ice is not a comfortable posture. Do not expect traction from your boot. The bike is most stable moving forward. Turn gingerly at first to get the feel for how the studs on your tires handle the arc. Using the front brake as a solo means of slowing is ill advised as you will go down quickly in a front skid. Some people have used traction devices on the bottoms of their boots. Experiment.

As a rule, studded tires are a monumental effort to mount and remove. This refers to both preparing for the ride and changing a flat tire in cold weather. Dedicated ice riders will purchase a second set of wheels dedicated to their studded tires; just sayin... 

Regarding the route. If time and conditions warrant, you might consider continuing on past Bog Meadow Pond into Black Rock Forest and riding Jim's Pond.

Of course you will need a Metro North bike permit.

Food and libation available further up 9D in Garrison at Garrison Pizza and the Gulf Station.

Do your homework, get studded tires, wait till the weather aligns, and join the esoteric sport of ice riding.

Thank you Brian for your dedication to this discipline and authoring this route.

HS 3/4/2021