delivered the opinion of the Court.
In Tennessee Coal Co. v. Muscoda Local, 321 U. S. 590, this Court held that underground travel in iron ore mines constituted work and hence was included in the compensable workweek within the meaning of Section 7 (a) of the Fair Labor Standards Act of 1938, 52 Stat. 1060, 1063, 29 U. S. C. § 207 (a). The sole issue in this case is whether any different result must be reached as regards underground travel in bituminous coal mines.
The petitioner, Jewell Ridge Coal Corporation, owns two bituminous coal mines in Virginia. It instituted this declaratory judgment action against the respondent unions and certain of their officials, representing all of petitioner’s underground mine workers. The respondents filed an answer and a counterclaim. By stipulation, *163the parties sought to determine “what constitutes the working time which makes up the workweek of plaintiff’s underground employees within the meaning of Section 7 of the Fair Labor Standards Act of 1938, and what amounts, if any, are due and unpaid to such employees under said Section, the determination of such amounts, if any, to be later referred to a special master.” This issue relates only to the work performed by petitioner’s underground miners between April 1, 1943, and June 20, 1943.
After hearing evidence and argument, the District Court concluded that petitioner had correctly computed the workweek on a “face to face” basis and that the Act did not require that the workweek include “either time spent by such employees outside the portal of the mines before entering therein, or time spent in traveling from the portals to their usual places of work and return.” 53 F. Supp. 935, 952. Only the issue as to travel time is involved here. The Fourth Circuit Court of Appeals felt that the Tennessee Coal case, which was decided by this Court subsequent to the entry of the District Court’s judgment in this proceeding, could not be distinguished in principle and accordingly reversed the judgment on that basis. 145 F. 2d 10.
We agree with the court below that there is no substantial factual or legal difference between this and the Tennessee Coal case and that underground travel in bituminous coal mines as well as in iron ore mines is included within the compensable workweek contemplated by § 7 (a) of the Fair Labor Standards Act.
Factually, underground travel between the portals and working faces of petitioner’s two bituminous coal mines bears all the indicia of work. While the District Court here'found “no such painful and burdensome conditions as those described in the iron ore mines,” 53 F. Supp. at 949, all three of the essential elements of work as set forth *164in the Tennessee Coal case, 321 U. S. at 598, are present in this instance:
1. Physical or mental exertion (whether burdensome or not). After arriving at petitioner’s mines by foot or vehicle, the miners first obtain their lamps from the lamp house near the main portal. They then enter the man trips at the portal and are transported down to the underground man trip stations — a journey varying in distance from 4,250 feet to 25,460 feet. Each man trip is composed of a train of small empty coal cars drawn by an electric motor or locomotive. From seven to eight men sit on a bench or on the floor of each car, which is only a few feet high. The cars, apparently are not overcrowded. If the roof of the passageway is sufficiently high the men are able to sit upright as they ride. But they must be on constant guard for the frequent low ceilings which force them to bend over to avoid striking their heads. And the dangers of falling slate and falling ceilings are ever present.
The District Court found that while this journey is “definitely not luxurious” it is “neither painful nor unduly uncomfortable, and is less hazardous than other phases of mining operations.” In this connection it should be noted that the record shows that six persons suffered com-pensable injuries, involving absence from work for seven days or more, while riding on petitioner’s man trips from January 1, 1939, to October 31, 1943. There is also evidence of two deaths and numerous minor injuries to the miners.
After arriving at the man trip stations, the miners check in at a nearby check-in board, a practice that differs inconsequentially from the procedure followed by the miners in the Tennessee Coal case of checking in at a tally house on the surface: They then collect their tools, equipment, explosives, etc., and carry them on foot to the working places, usually some 500 to 1,500 feet away. This requires that they proceed through dark and dangerous *165tunnels, often so low as to force them to crouch over while carrying their burdens. Moreover, they must keep constant vigil against live electric wires, falling rocks and obstacles under foot. At the end of each shift, the miners make their return journey to the man trip stations, deposit their tools and equipment and ascend to the portal via the man trips.
In addition, approximately 72 men at petitioner’s Jewell Ridge mine enter the mine at places other than the main portal and either catch the man trips at some man trip station inside the mine or walk all the way to their places of work.
These undisputed facts compel the conclusion that the underground travel in petitioner’s mines involves physical and mental exertion. That it may not be so burdensome or disagreeable as some of the aspects of the travel described in the Tennessee Coal case is not of controlling significance in this respect.
2. Exertion controlled or required by the employer. It is obvious that the underground travel is both controlled and required by petitioner. Both the man trip transportation and travel by foot occur solely on petitioner’s property and occur only as and when required by petitioner. Petitioner organizes, operates and supervises all aspects of the man trips. Definite schedules are arranged and maintained by petitioner. A company foreman rides on each man trip and occasionally gives work instructions during the journey. He also compels compliance with the numerous safety rules for man trips adopted by petitioner in compliance with state law. Layoff or discharge may result from a miner’s continued failure to obey these rules.
3. Exertion pursued necessarily and primarily for the benefit of the employer and his business. It is too obvious to require extended discussion that here, as in the Tennessee Coal case, the underground travel is undertaken *166necessarily and primarily for the benefit of petitioner and its coal mining operations. The miners do not engage in this travel for their own pleasure or convenience. It occurs only because it is a necessary prerequisite to the extraction of coal from the mines, which is the prime purpose of petitioner’s business. Without such travel the coal could not be mined.
Thus the three basic elements of work of a type necessarily included within the workweek as contemplated by the Act are plainly evident from these facts. Those who are forced to travel in underground mines in order to earn their livelihood are unlike the ordinary traveler or the ordinary workman on his way to work. They must journey beneath the crust of the earth, far removed from the fresh and open air and from the beneficial rays of the sun. A heavy toll is exacted from those whose lot it is to ride and walk and mine beneath the surface. From the moment they enter the portal until they leave they are subjected to constant hazards and dangers; they are left begrimed and exhausted by their continuous physical and mental exertion.
To conclude that such subterraneous travel is not work is to ignore reality completely. We therefore are compelled to hold that the only reasonable conclusion to be drawn from the District Court’s findings of fact and from other undisputed evidence is that the underground travel in petitioner’s two mines is work and that the time spent in such travel should be included within the workweek for purposes of § 7 (a) of the Fair Labor Standards Act.
The other propositions advanced by petitioner are also answered by the principles of the Tennessee Coal case. Thus petitioner places heavy reliance upon the conclusion of the District Court that “by the universal custom and usage of the past fifty years, and by agreement of the parties in every collective bargaining agreement which was ever made, it was universally recognized that in the bituminous coal industry, travel time was not work time.” *16753 F. Supp. at 950. But even though the customs and contracts prevalent in this industry were to compute the workday only from the time spent “face to face” with the seams, we need only repeat what we said on this subject in the Tennessee Coal opinion, 321 U. S. at 602: “But in any event it is immaterial that there may have been a prior custom or contract not to consider certain work within the compass of the workweek or not to compensate employees for certain portions of their work. The Fair Labor Standards Act was not designed to codify or perpetuate those customs and contracts which allow an employer to claim all of an employee's time while compensating him only for a part of it. Congress intended, instead, to achieve a uniform national policy of guaranteeing compensation for all work or employment engaged in by employees covered by the Act. Any custom or contract falling short of that basic policy, like an agreement to pay less than the minimum wage requirements, cannot be utilized to deprive employees of their statutory rights.”
Such a conclusion is the only method of achieving the plain design of § 7 (a) to spread employment through imposing the overtime pay requirement on the employer and to compensate the employee for the burden of a workweek in excess of the hours fixed by the Act. Walling v. Helmerich & Payne, 323 U. S. 37, 40; Overnight Motor Co. v. Missel, 316 U. S. 572, 577, 578. This necessitates that the workweek be computed on the basis of the hours spent in actual work and that compensation be paid accordingly. And even those employers who pay wages above the minimum and who maintain no substandard working conditions must respect this statutory pattern. Conversely, employees are not to be deprived of the benefits of the Act simply because they are well paid or because they are represented by strong bargaining agents. This may in some instances require certain modifications and adjustments in existing customs and contracts in order to include all the hours actually worked in the statutory *168workweek or to compensate at the proper rate for all of such labor. But if these modifications and adjustments are not made, the plain language and policy of § 7 (a) are frustrated.
Petitioner here has presented no cogent reason for legalizing such a frustration, however unintentional in character, of the statutory scheme. Statements in the legislative history to the effect that the Act was aimed primarily at overworked and underpaid workers and that the Act did not attempt to interfere with bona fide collective bargaining agreements are indecisive of the issue in the present case.1 Such general remarks, when read fairly and in *169light of their true context, were obviously not made with this narrow issue in mind and they cannot be said to demonstrate a Congressional desire to allow the coal industry to use private customs and agreements as an excuse for failure to compute the workweek as contemplated by § 7 (a). In fact, some of these statements expressly recognize the necessity of modifying or setting aside those collective agreements that did not conform with statutory standards.2
Nor can we give weight to the fact that the Administrator of the Wage and Hour Division in 1940 issued a public statement that he would not regard the practice of computing working time on a “face to face” basis in the bituminous coal industry as unreasonable in light of the prevailing customs and practices, supported by a long history of bona fide collective bargaining. This statement, being legally untenable, lacks the usual respect to be accorded the Administrator’s rulings, interpretations and opinions. Cf. Skidmore v. Swift & Co., 323 U. S. 134, 140.
Moreover, as in the Tennessee Coal case, we are not concerned here with the use of bona fide contracts or customs *170to settle difficult and doubtful questions as to whether certain activity or nonactivity constitutes work. Cf. Armour & Co. v. Wantock, 323 U. S. 126. Nor do we make any intimations at this time concerning the validity of agreements whereby, in a bona fide attempt to avoid complex difficulties of computation, travel time is averaged or fixed at an arbitrary figure and underground miners are paid on that basis rather than according to their individual travel time.
We are dealing here solely with a set of facts that leaves no reasonable doubt that underground travel in petitioner's two bituminous coal mines partakes of the very essence of work.3 This travel must therefore be included within the workweek for purposes of § 7 (a) of the Fair Labor Standards Act regardless of any custom or contract to the contrary at the time in question. Thus shall each of petitioner's miners receive his own reward according to his own labor.
Affirmed.
Thus, for example, the District Court relied in part upon a statement made by the Senator in charge of the original bill, which did not become law as it was then framed, to the effect that the bill did not affect collective agreements already made or hereafter to be made between employer and employee. 81 Cong. Rec. 7650. Aside from the fact that this statement was made with reference to entirely different provisions than those presently in the Act, a full and fair reading of the entire debate at the time in question demonstrates that the possibility of affecting or setting aside collective agreements when they did not coincide with statutory standards was definitely understood and appreciated. This is shown by the following remarks (81 Cong. Rec. 7650):
“Mr. Walsh. Next, does the bill affect collective-bargaining agreements already made or hereafter to be made between employers and employees ?
“Mr. Black. It does not.
“Mr. Walsh. There is one exception to that, is there not? The bill does not affect collective-bargaining agreements where the hours are less than 40 per week, or where the wages are more than 40 cents per hour?
“Mr. Black. That is correct.
“Mr. Walsh. But if a collective-bargaining agreement has been entered into at 36 cents per hour wages, the board would have jurisdiction to set that agreement aside and to fix, if the facts warrant it, a minimum wage of 40 cents?” (Italics added.)
“Mr. Black. The board would have jurisdiction to do it, but under the provisions of the law it would be my judgment that the *169board would be very reluctant, indeed, to attempt to interfere with a bona-fide agreement made between employer and employee.
“Mr. Walsh. I think the Senator is correct; but the situation might well exist that the board, in fixing a minimum wage in a case where the wage of the employees was less than 40 cents, after a survey and study of the question, and taking into consideration some factors that it must take into consideration in fixing the wage, might decide, let us say, upon 38 cents per hour. If it is found that in some other industry of like character and nature there was a collective-bargaining agreement providing for the payment of 36 cents an hour it would, would it not, take jurisdiction and set aside that collective-bargaining agreement insofar as the facts showed that 38 cents was a fair rate?” (Italics added.)
“Mr. Black. It would.”
See note 1, supra.
Indeed, to the extent that petitioner’s “face to face” collective bargaining agreements excluded travel time from the compensable workweek there was an implied recognition that underground travel was work and that such work would normally call for additional compensation in the absence of a specific “face to face” provision to the contrary. And the widespread practice in other coal producing nations of including travel time or portions thereof in the workday further bears out the conclusion that underground travel is work.