I second cnwrobb's post. In my callow youth (age 19), I worked for the Pennsy as an Electric Traction Electrician's Helper (which only rarely took place indoors).
It was daring, exciting work, involving Demolition, HV catenary and transmission electrical construction and maintenance, and also maintenance and repair in under river tunnels (salt water stalactites (Saltsicles) can ground out the overhead wire, and a locomotive's damaged pantograph can rip out hundreds of yards of catenary wire supporting insulators. I was tasked to work in each situation.); as well as maintaining aircraft collision avoidance lamps atop transmission towers, and catenary wire maintenance on some pretty tall bridges. I worked several times outside the railed-in safety zone atop the Newark Bay Bridge, 490-ish feet above the water (salt fog can be destructive and dangerous in a HV environment).
The work environment involves forces, energies, distances,and masses several orders of magnitude larger than the average Joe will ever encounter, or even contemplate, in an entire lifetime.
Height wasn't something I ever became accustomed to, even to this day, but the job is whatever the Boss says it is; and when he says "climb", you climb until he says "stop". Ignoring an order in some jobs can get you killed right quick.
The lowest AC voltage we worked on was 6600V (signal) and the greatest was 66KV (transmission) with the most prevalent catenary (locomotive pickup current) being 11KV, while any yard/tunnel work often involved also working amidst uncovered 440VDC third rail power.
One learned to count rails, and stepping on any rail, anywhere, was grounds for immediate termination. There's so much more going on electrically along the rails than most folks ever imagine.
For one example, the rails provide the return path for the 11KV overhead traction current, and carry the full amperage required to drive an entire Electric Train. Never step on a rail, one defective electrical bonding strap connecting each rail section anywhere between the train and the electrical substation could end one too quickly for them to even notice they are dead. That stuff is not your tame and comparatively measly house current. the wiring involved usually employed solid copper rod bout as thick as one's index finger, and sections needed to be isolated and then grounded to the rail before work could commence, induction current from adjacent conductors could be several times that of a lethal level.
Also true to his post, I left in six months (following a fatality right above me on the tower, partway (about 100ft) up during a callout in the midst of a hurricane). The day following the fatality, I came back to second shift and gave notice, with a job offer from IBM already in hand. They were always decent folks to work alongside and they released me from serving out my notice on the spot. The previous day had been difficult for all of us, and they were sympathetic to a Brother in genuine distress.
On another occasion, I worked four days and nights straight through inside one of the two PRR tunnels under the Hudson; wielding a jackhammer into the roof of a concrete tube with the Hudson river one the other side of the (several feet thick) concrete tunnel tube (which was originally lowered onto the riverbed and joined/sealed by divers).
The experience was highly educational and looking back, I suspect it also had a distinct formative effect on my character, as well as instilling a healthy sense of caution in areas of hazard.
I also got drafted into Corps about three months later, and sure enough they classified me as a pole line electrician despite my fresh graduation from electric typewriter repair school.
The brotherhood of shared hazard I had experienced on the Pennsy was a very good preparation for the same some kind of camaraderie I was to find in the Corps.
All I all, I still recommend the RR field, but I also caution prospects that the work they can expect can be dirty, strenuous, and can also include some significant hazard on a frequent basis. Some will turn away, and other will embrace the concept, and each will be wise in their own situation. Whichever one chooses, I'd say it would be wisest to research the work environment before making any lasting commitments to it.
Greg